21320531623 has 8 divisors (see below), whose sum is σ = 22774458528. Its totient is φ = 19888802304.

The previous prime is 21320531597. The next prime is 21320531627. The reversal of 21320531623 is 32613502312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21320531623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21320531591 and 21320531600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320531627) 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 7 ways as a sum of consecutive naturals, for example, 5547411 + ... + 5551252.

It is an arithmetic number, because the mean of its divisors is an integer number (2846807316).

Almost surely, 2^21320531623 is an apocalyptic number.

21320531623 is a deficient number, since it is larger than the sum of its proper divisors (1453926905).

21320531623 is a wasteful number, since it uses less digits than its factorization.

21320531623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11098793.

The product of its (nonzero) digits is 6480, while the sum is 28.

The spelling of 21320531623 in words is "twenty-one billion, three hundred twenty million, five hundred thirty-one thousand, six hundred twenty-three".