31012232221 has 8 divisors (see below), whose sum is σ = 31626336600. Its totient is φ = 30399200832.

The previous prime is 31012232219. The next prime is 31012232257. The reversal of 31012232221 is 12223221013.

It can be written as a sum of positive squares in 4 ways, for example, as 17852700996 + 13159531225 = 133614^2 + 114715^2 .

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 31012232221 - 2¹ = 31012232219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31012232291) 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, 209746 + ... + 325603.

It is an arithmetic number, because the mean of its divisors is an integer number (3953292075).

Almost surely, 2^31012232221 is an apocalyptic number.

It is an amenable number.

31012232221 is a deficient number, since it is larger than the sum of its proper divisors (614104379).

31012232221 is a wasteful number, since it uses less digits than its factorization.

31012232221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536495.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 31012232221 its reverse (12223221013), we get a palindrome (43235453234).

It can be divided in two parts, 3101 and 2232221, that added together give a palindrome (2235322).

The spelling of 31012232221 in words is "thirty-one billion, twelve million, two hundred thirty-two thousand, two hundred twenty-one".