21231431031 has 8 divisors (see below), whose sum is σ = 29539382400. Its totient is φ = 13538883512.

The previous prime is 21231431029. The next prime is 21231431069. The reversal of 21231431031 is 13013413212.

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 21231431031 - 2¹ = 21231431029 is a prime.

It is a super-2 number, since 2×21231431031² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21231430989 and 21231431007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231431731) 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, 153850881 + ... + 153851018.

It is an arithmetic number, because the mean of its divisors is an integer number (3692422800).

Almost surely, 2^21231431031 is an apocalyptic number.

21231431031 is a deficient number, since it is larger than the sum of its proper divisors (8307951369).

21231431031 is a wasteful number, since it uses less digits than its factorization.

21231431031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307701925.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 21231431031 its reverse (13013413212), we get a palindrome (34244844243).

The spelling of 21231431031 in words is "twenty-one billion, two hundred thirty-one million, four hundred thirty-one thousand, thirty-one".