31400189 has 2 divisors, whose sum is σ = 31400190. Its totient is φ = 31400188.

The previous prime is 31400167. The next prime is 31400231. The reversal of 31400189 is 98100413.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21696964 + 9703225 = 4658^2 + 3115^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31400189 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31400119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15700094 + 15700095.

It is an arithmetic number, because the mean of its divisors is an integer number (15700095).

Almost surely, 2^31400189 is an apocalyptic number.

It is an amenable number.

31400189 is a deficient number, since it is larger than the sum of its proper divisors (1).

31400189 is an equidigital number, since it uses as much as digits as its factorization.

31400189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 31400189 is about 5603.5871546716. The cubic root of 31400189 is about 315.4840596626.

The spelling of 31400189 in words is "thirty-one million, four hundred thousand, one hundred eighty-nine".