61189039440 has 400 divisors, whose sum is σ = 225150024000. Its totient is φ = 15358408704.

The previous prime is 61189039393. The next prime is 61189039441. The reversal of 61189039440 is 4493098116.

61189039440 is a `hidden beast` number, since 6 + 118 + 90 + 3 + 9 + 440 = 666.

61189039440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61189039441) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 20067036 + ... + 20070084.

It is an arithmetic number, because the mean of its divisors is an integer number (562875060).

Almost surely, 2^61189039440 is an apocalyptic number.

61189039440 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 61189039440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112575012000).

61189039440 is an abundant number, since it is smaller than the sum of its proper divisors (163960984560).

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

61189039440 is a wasteful number, since it uses less digits than its factorization.

61189039440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3256 (or 3241 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 61189039440 in words is "sixty-one billion, one hundred eighty-nine million, thirty-nine thousand, four hundred forty".