21907699431 has 4 divisors (see below), whose sum is σ = 29210265912. Its totient is φ = 14605132952.

The previous prime is 21907699391. The next prime is 21907699481. The reversal of 21907699431 is 13499670912.

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 21907699431 - 2³⁰ = 20833957607 is a prime.

It is a super-2 number, since 2×21907699431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21907699481) 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, 3651283236 + ... + 3651283241.

It is an arithmetic number, because the mean of its divisors is an integer number (7302566478).

Almost surely, 2^21907699431 is an apocalyptic number.

21907699431 is a deficient number, since it is larger than the sum of its proper divisors (7302566481).

21907699431 is an equidigital number, since it uses as much as digits as its factorization.

21907699431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7302566480.

The product of its (nonzero) digits is 734832, while the sum is 51.

The spelling of 21907699431 in words is "twenty-one billion, nine hundred seven million, six hundred ninety-nine thousand, four hundred thirty-one".