31021012221 has 8 divisors (see below), whose sum is σ = 41366334720. Its totient is φ = 20678182272.

The previous prime is 31021012219. The next prime is 31021012279. The reversal of 31021012221 is 12221012013.

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

It is not a de Polignac number, because 31021012221 - 2¹ = 31021012219 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31021012221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31021012721) 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, 593901 + ... + 644018.

It is an arithmetic number, because the mean of its divisors is an integer number (5170791840).

Almost surely, 2^31021012221 is an apocalyptic number.

It is an amenable number.

31021012221 is a deficient number, since it is larger than the sum of its proper divisors (10345322499).

31021012221 is a wasteful number, since it uses less digits than its factorization.

31021012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1246275.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 31021012221 its reverse (12221012013), we get a palindrome (43242024234).

The spelling of 31021012221 in words is "thirty-one billion, twenty-one million, twelve thousand, two hundred twenty-one".