31000129 has 4 divisors (see below), whose sum is σ = 32823684. Its totient is φ = 29176576.

The previous prime is 31000127. The next prime is 31000157. The reversal of 31000129 is 92100013.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16000000 + 15000129 = 4000^2 + 3873^2 .

It is a cyclic number.

It is not a de Polignac number, because 31000129 - 2¹ = 31000127 is a prime.

It is a super-2 number, since 2×31000129² = 1922015996033282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31000127) 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, 911752 + ... + 911785.

It is an arithmetic number, because the mean of its divisors is an integer number (8205921).

Almost surely, 2^31000129 is an apocalyptic number.

It is an amenable number.

31000129 is a deficient number, since it is larger than the sum of its proper divisors (1823555).

31000129 is a wasteful number, since it uses less digits than its factorization.

31000129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1823554.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 31000129 is about 5567.7759473600. The cubic root of 31000129 is about 314.1385009784.

The spelling of 31000129 in words is "thirty-one million, one hundred twenty-nine", and thus it is an aban number.