61212187920 has 160 divisors (see below), whose sum is σ = 206817512832. Its totient is φ = 14886014976.

The previous prime is 61212187903. The next prime is 61212187931. The reversal of 61212187920 is 2978121216.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 140772 + ... + 377148.

Almost surely, 2^61212187920 is an apocalyptic number.

61212187920 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 61212187920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103408756416).

61212187920 is an abundant number, since it is smaller than the sum of its proper divisors (145605324912).

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

61212187920 is a wasteful number, since it uses less digits than its factorization.

61212187920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236489 (or 236483 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The spelling of 61212187920 in words is "sixty-one billion, two hundred twelve million, one hundred eighty-seven thousand, nine hundred twenty".