21690624351 has 16 divisors (see below), whose sum is σ = 31750962048. Its totient is φ = 13062098400.

The previous prime is 21690624349. The next prime is 21690624353. The reversal of 21690624351 is 15342609612.

It is an interprime number because it is at equal distance from previous prime (21690624349) and next prime (21690624353).

It is not a de Polignac number, because 21690624351 - 2¹ = 21690624349 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21690624353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2088105 + ... + 2098466.

It is an arithmetic number, because the mean of its divisors is an integer number (1984435128).

Almost surely, 2^21690624351 is an apocalyptic number.

21690624351 is a deficient number, since it is larger than the sum of its proper divisors (10060337697).

21690624351 is a wasteful number, since it uses less digits than its factorization.

21690624351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4186742.

The product of its (nonzero) digits is 77760, while the sum is 39.

The spelling of 21690624351 in words is "twenty-one billion, six hundred ninety million, six hundred twenty-four thousand, three hundred fifty-one".