64187801931977 has 8 divisors (see below), whose sum is σ = 68195800749000. Its totient is φ = 60299444870784.

The previous prime is 64187801931887. The next prime is 64187801932021. The reversal of 64187801931977 is 77913910878146.

It can be written as a sum of positive squares in 4 ways, for example, as 46263789459001 + 17924012472976 = 6801749^2 + 4233676^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 64187801931977 - 2¹⁸ = 64187801669833 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64187801931977.

It is not an unprimeable number, because it can be changed into a prime (64187801931377) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29910437852 + ... + 29910439997.

It is an arithmetic number, because the mean of its divisors is an integer number (8524475093625).

Almost surely, 2^{64187801931977} is an apocalyptic number.

It is an amenable number.

64187801931977 is a deficient number, since it is larger than the sum of its proper divisors (4007998817023).

64187801931977 is a wasteful number, since it uses less digits than its factorization.

64187801931977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59820877915.

The product of its (nonzero) digits is 128024064, while the sum is 71.

The spelling of 64187801931977 in words is "sixty-four trillion, one hundred eighty-seven billion, eight hundred one million, nine hundred thirty-one thousand, nine hundred seventy-seven".