31021140221 has 4 divisors (see below), whose sum is σ = 32369885472. Its totient is φ = 29672394972.

The previous prime is 31021140217. The next prime is 31021140247. The reversal of 31021140221 is 12204112013.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31021140221 - 2² = 31021140217 is a prime.

It is a super-2 number, since 2×31021140221² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31021140221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31021149221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 674372591 + ... + 674372636.

It is an arithmetic number, because the mean of its divisors is an integer number (8092471368).

Almost surely, 2^31021140221 is an apocalyptic number.

It is an amenable number.

31021140221 is a deficient number, since it is larger than the sum of its proper divisors (1348745251).

31021140221 is a wasteful number, since it uses less digits than its factorization.

31021140221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1348745250.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 31021140221 its reverse (12204112013), we get a palindrome (43225252234).

The spelling of 31021140221 in words is "thirty-one billion, twenty-one million, one hundred forty thousand, two hundred twenty-one".