61690755409920 has 3456 divisors, whose sum is σ = 289099064217600. Its totient is φ = 12319835553792.

The previous prime is 61690755409889. The next prime is 61690755409937. The reversal of 61690755409920 is 2990455709616.

61690755409920 is a `hidden beast` number, since 6 + 1 + 6 + 90 + 7 + 55 + 409 + 92 + 0 = 666.

61690755409920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (3456).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 55929968089 + ... + 55929969191.

It is an arithmetic number, because the mean of its divisors is an integer number (83651349600).

Almost surely, 2^{61690755409920} is an apocalyptic number.

61690755409920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61690755409920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144549532108800).

61690755409920 is an abundant number, since it is smaller than the sum of its proper divisors (227408308807680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61690755409920 is a wasteful number, since it uses less digits than its factorization.

61690755409920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1197 (or 1152 counting only the distinct ones).

The product of its (nonzero) digits is 36741600, while the sum is 63.

The spelling of 61690755409920 in words is "sixty-one trillion, six hundred ninety billion, seven hundred fifty-five million, four hundred nine thousand, nine hundred twenty".