20787757477902 has 64 divisors (see below), whose sum is σ = 48926285547840. Its totient is φ = 6519794070528.

The previous prime is 20787757477901. The next prime is 20787757477957. The reversal of 20787757477902 is 20977475778702.

20787757477902 is a `hidden beast` number, since 2 + 0 + 7 + 87 + 75 + 7 + 477 + 9 + 0 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20787757477901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9298 + ... + 6447914.

It is an arithmetic number, because the mean of its divisors is an integer number (764473211685).

Almost surely, 2^{20787757477902} is an apocalyptic number.

20787757477902 is an abundant number, since it is smaller than the sum of its proper divisors (28138528069938).

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

20787757477902 is a wasteful number, since it uses less digits than its factorization.

20787757477902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6442162 (or 6442156 counting only the distinct ones).

The product of its (nonzero) digits is 677658240, while the sum is 72.

The spelling of 20787757477902 in words is "twenty trillion, seven hundred eighty-seven billion, seven hundred fifty-seven million, four hundred seventy-seven thousand, nine hundred two".