61864459520 has 36 divisors (see below), whose sum is σ = 148184716260. Its totient is φ = 24745783296.

The previous prime is 61864459471. The next prime is 61864459561. The reversal of 61864459520 is 2595446816.

It can be written as a sum of positive squares in 2 ways, for example, as 15056271616 + 46808187904 = 122704^2 + 216352^2 .

It is a super-2 number, since 2×61864459520² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24164525 + ... + 24167084.

Almost surely, 2^61864459520 is an apocalyptic number.

It is an amenable number.

61864459520 is an abundant number, since it is smaller than the sum of its proper divisors (86320256740).

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

61864459520 is an equidigital number, since it uses as much as digits as its factorization.

61864459520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48331630 (or 48331616 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 50.

The spelling of 61864459520 in words is "sixty-one billion, eight hundred sixty-four million, four hundred fifty-nine thousand, five hundred twenty".