31998151 has 2 divisors, whose sum is σ = 31998152. Its totient is φ = 31998150.

The previous prime is 31998143. The next prime is 31998157. The reversal of 31998151 is 15189913.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31998151 - 2³ = 31998143 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31998151.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31998157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15999075 + 15999076.

It is an arithmetic number, because the mean of its divisors is an integer number (15999076).

Almost surely, 2^31998151 is an apocalyptic number.

31998151 is a deficient number, since it is larger than the sum of its proper divisors (1).

31998151 is an equidigital number, since it uses as much as digits as its factorization.

31998151 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9720, while the sum is 37.

The square root of 31998151 is about 5656.6908170767. The cubic root of 31998151 is about 317.4740954747.

It can be divided in two parts, 3 and 1998151, that multiplied together give a triangular number (5994453 = T₃₄₆₂).

The spelling of 31998151 in words is "thirty-one million, nine hundred ninety-eight thousand, one hundred fifty-one".