10031021221 has 16 divisors (see below), whose sum is σ = 10921310064. Its totient is φ = 9158183424.

The previous prime is 10031021171. The next prime is 10031021237. The reversal of 10031021221 is 12212013001.

It can be written as a sum of positive squares in 8 ways, for example, as 8208225 + 10022812996 = 2865^2 + 100114^2 .

It is not a de Polignac number, because 10031021221 - 2⁷ = 10031021093 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10031021251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 483171 + ... + 503503.

It is an arithmetic number, because the mean of its divisors is an integer number (682581879).

Almost surely, 2^10031021221 is an apocalyptic number.

It is an amenable number.

10031021221 is a deficient number, since it is larger than the sum of its proper divisors (890288843).

10031021221 is a wasteful number, since it uses less digits than its factorization.

10031021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20760.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 10031021221 its reverse (12212013001), we get a palindrome (22243034222).

The spelling of 10031021221 in words is "ten billion, thirty-one million, twenty-one thousand, two hundred twenty-one".