20787757477563 has 16 divisors (see below), whose sum is σ = 27722739451680. Its totient is φ = 13855640553216.

The previous prime is 20787757477537. The next prime is 20787757477573. The reversal of 20787757477563 is 36577475778702.

It is not a de Polignac number, because 20787757477563 - 2⁶ = 20787757477499 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20787757477573) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 396255631 + ... + 396308087.

It is an arithmetic number, because the mean of its divisors is an integer number (1732671215730).

Almost surely, 2^{20787757477563} is an apocalyptic number.

20787757477563 is a deficient number, since it is larger than the sum of its proper divisors (6934981974117).

20787757477563 is a wasteful number, since it uses less digits than its factorization.

20787757477563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77246.

The product of its (nonzero) digits is 3388291200, while the sum is 75.

The spelling of 20787757477563 in words is "twenty trillion, seven hundred eighty-seven billion, seven hundred fifty-seven million, four hundred seventy-seven thousand, five hundred sixty-three".