31459891 has 2 divisors, whose sum is σ = 31459892. Its totient is φ = 31459890.

The previous prime is 31459859. The next prime is 31459931. The reversal of 31459891 is 19895413.

It is an a-pointer prime, because the next prime (31459931) can be obtained adding 31459891 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31459891 - 2⁵ = 31459859 is a prime.

It is not a weakly prime, because it can be changed into another prime (31459291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15729945 + 15729946.

It is an arithmetic number, because the mean of its divisors is an integer number (15729946).

Almost surely, 2^31459891 is an apocalyptic number.

31459891 is a deficient number, since it is larger than the sum of its proper divisors (1).

31459891 is an equidigital number, since it uses as much as digits as its factorization.

31459891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 40.

The square root of 31459891 is about 5608.9117482806. The cubic root of 31459891 is about 315.6838791048.

The spelling of 31459891 in words is "thirty-one million, four hundred fifty-nine thousand, eight hundred ninety-one".