21076864157 has 2 divisors, whose sum is σ = 21076864158. Its totient is φ = 21076864156.

The previous prime is 21076864153. The next prime is 21076864169. The reversal of 21076864157 is 75146867012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19202753476 + 1874110681 = 138574^2 + 43291^2 .

It is a cyclic number.

It is not a de Polignac number, because 21076864157 - 2² = 21076864153 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21076864153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10538432078 + 10538432079.

It is an arithmetic number, because the mean of its divisors is an integer number (10538432079).

Almost surely, 2^21076864157 is an apocalyptic number.

It is an amenable number.

21076864157 is a deficient number, since it is larger than the sum of its proper divisors (1).

21076864157 is an equidigital number, since it uses as much as digits as its factorization.

21076864157 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 564480, while the sum is 47.

The spelling of 21076864157 in words is "twenty-one billion, seventy-six million, eight hundred sixty-four thousand, one hundred fifty-seven".