31081151321 has 4 divisors (see below), whose sum is σ = 33906710544. Its totient is φ = 28255592100.

The previous prime is 31081151317. The next prime is 31081151341. The reversal of 31081151321 is 12315118013.

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 31081151321 - 2² = 31081151317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31081151341) 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, 1412779595 + ... + 1412779616.

It is an arithmetic number, because the mean of its divisors is an integer number (8476677636).

Almost surely, 2^31081151321 is an apocalyptic number.

It is an amenable number.

31081151321 is a deficient number, since it is larger than the sum of its proper divisors (2825559223).

31081151321 is a wasteful number, since it uses less digits than its factorization.

31081151321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2825559222.

The product of its (nonzero) digits is 720, while the sum is 26.

Adding to 31081151321 its reverse (12315118013), we get a palindrome (43396269334).

The spelling of 31081151321 in words is "thirty-one billion, eighty-one million, one hundred fifty-one thousand, three hundred twenty-one".