20515776653261 has 16 divisors (see below), whose sum is σ = 21269940007680. Its totient is φ = 19773710964480.

The previous prime is 20515776653257. The next prime is 20515776653269. The reversal of 20515776653261 is 16235667751502.

It is not a de Polignac number, because 20515776653261 - 2² = 20515776653257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20515776653197 and 20515776653206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20515776653269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196774001 + ... + 196878233.

It is an arithmetic number, because the mean of its divisors is an integer number (1329371250480).

Almost surely, 2^{20515776653261} is an apocalyptic number.

It is an amenable number.

20515776653261 is a deficient number, since it is larger than the sum of its proper divisors (754163354419).

20515776653261 is a wasteful number, since it uses less digits than its factorization.

20515776653261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162196.

The product of its (nonzero) digits is 15876000, while the sum is 56.

The spelling of 20515776653261 in words is "twenty trillion, five hundred fifteen billion, seven hundred seventy-six million, six hundred fifty-three thousand, two hundred sixty-one".