31616121 has 4 divisors (see below), whose sum is σ = 42154832. Its totient is φ = 21077412.

The previous prime is 31616113. The next prime is 31616129. The reversal of 31616121 is 12161613.

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 an interprime number because it is at equal distance from previous prime (31616113) and next prime (31616129).

It is not a de Polignac number, because 31616121 - 2³ = 31616113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31616129) 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, 5269351 + ... + 5269356.

It is an arithmetic number, because the mean of its divisors is an integer number (10538708).

Almost surely, 2^31616121 is an apocalyptic number.

It is an amenable number.

31616121 is a deficient number, since it is larger than the sum of its proper divisors (10538711).

31616121 is a wasteful number, since it uses less digits than its factorization.

31616121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10538710.

The product of its digits is 216, while the sum is 21.

The square root of 31616121 is about 5622.8214447909. The cubic root of 31616121 is about 316.2055791213.

Adding to 31616121 its reverse (12161613), we get a palindrome (43777734).

It can be divided in two parts, 3161612 and 1, that added together give a palindrome (3161613).

The spelling of 31616121 in words is "thirty-one million, six hundred sixteen thousand, one hundred twenty-one".