31139851 has 8 divisors (see below), whose sum is σ = 31506464. Its totient is φ = 30775680.

The previous prime is 31139821. The next prime is 31139863. The reversal of 31139851 is 15893113.

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 31139851 - 2¹¹ = 31137803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31139821) 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, 37426 + ... + 38248.

It is an arithmetic number, because the mean of its divisors is an integer number (3938308).

Almost surely, 2^31139851 is an apocalyptic number.

31139851 is a deficient number, since it is larger than the sum of its proper divisors (366613).

31139851 is a wasteful number, since it uses less digits than its factorization.

31139851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1221.

The product of its digits is 3240, while the sum is 31.

The square root of 31139851 is about 5580.3092208228. The cubic root of 31139851 is about 314.6097493579.

The spelling of 31139851 in words is "thirty-one million, one hundred thirty-nine thousand, eight hundred fifty-one".