61557706764 has 36 divisors (see below), whose sum is σ = 155614098640. Its totient is φ = 20517930720.

The previous prime is 61557706751. The next prime is 61557706783. The reversal of 61557706764 is 46760775516.

61557706764 is a `hidden beast` number, since 6 + 1 + 5 + 577 + 0 + 6 + 7 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×61557706764² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 61557706764.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 641649 + ... + 731319.

Almost surely, 2^61557706764 is an apocalyptic number.

It is an amenable number.

61557706764 is an abundant number, since it is smaller than the sum of its proper divisors (94056391876).

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

61557706764 is a wasteful number, since it uses less digits than its factorization.

61557706764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108750 (or 108745 counting only the distinct ones).

The product of its (nonzero) digits is 7408800, while the sum is 54.

The spelling of 61557706764 in words is "sixty-one billion, five hundred fifty-seven million, seven hundred six thousand, seven hundred sixty-four".