31221034431 has 8 divisors (see below), whose sum is σ = 41633984640. Its totient is φ = 20811053592.

The previous prime is 31221034373. The next prime is 31221034487. The reversal of 31221034431 is 13443012213.

It is a happy number.

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

It is not a de Polignac number, because 31221034431 - 2⁷ = 31221034303 is a prime.

It is a super-2 number, since 2×31221034431² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31221034331) 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, 717691 + ... + 759948.

It is an arithmetic number, because the mean of its divisors is an integer number (5204248080).

Almost surely, 2^31221034431 is an apocalyptic number.

31221034431 is a deficient number, since it is larger than the sum of its proper divisors (10412950209).

31221034431 is a wasteful number, since it uses less digits than its factorization.

31221034431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1484685.

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 31221034431 its reverse (13443012213), we get a palindrome (44664046644).

The spelling of 31221034431 in words is "thirty-one billion, two hundred twenty-one million, thirty-four thousand, four hundred thirty-one".