21086550774631 has 4 divisors (see below), whose sum is σ = 21086570324664. Its totient is φ = 21086531224600.

The previous prime is 21086550774629. The next prime is 21086550774647. The reversal of 21086550774631 is 13647705568012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21086550774631 - 2¹ = 21086550774629 is a prime.

It is a super-2 number, since 2×21086550774631² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21086550774031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8056405 + ... + 10347886.

It is an arithmetic number, because the mean of its divisors is an integer number (5271642581166).

Almost surely, 2^{21086550774631} is an apocalyptic number.

21086550774631 is a deficient number, since it is larger than the sum of its proper divisors (19550033).

21086550774631 is a wasteful number, since it uses less digits than its factorization.

21086550774631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19550032.

The product of its (nonzero) digits is 8467200, while the sum is 55.

The spelling of 21086550774631 in words is "twenty-one trillion, eighty-six billion, five hundred fifty million, seven hundred seventy-four thousand, six hundred thirty-one".