21312232031 has 8 divisors (see below), whose sum is σ = 21674652480. Its totient is φ = 20952127872.

The previous prime is 21312232021. The next prime is 21312232063. The reversal of 21312232031 is 13023221312.

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

It is a cyclic number.

It is not a de Polignac number, because 21312232031 - 2¹⁴ = 21312215647 is a prime.

It is a super-4 number, since 4×21312232031⁴ (a number of 42 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21312231994 and 21312232012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312232001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 560510 + ... + 597323.

It is an arithmetic number, because the mean of its divisors is an integer number (2709331560).

Almost surely, 2^21312232031 is an apocalyptic number.

21312232031 is a deficient number, since it is larger than the sum of its proper divisors (362420449).

21312232031 is a wasteful number, since it uses less digits than its factorization.

21312232031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1158145.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21312232031 its reverse (13023221312), we get a palindrome (34335453343).

The spelling of 21312232031 in words is "twenty-one billion, three hundred twelve million, two hundred thirty-two thousand, thirty-one".