30881999 has 2 divisors, whose sum is σ = 30882000. Its totient is φ = 30881998.

The previous prime is 30881971. The next prime is 30882001. The reversal of 30881999 is 99918803.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 30881999 - 2¹⁶ = 30816463 is a prime.

Together with 30882001, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30880999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15440999 + 15441000.

It is an arithmetic number, because the mean of its divisors is an integer number (15441000).

Almost surely, 2^30881999 is an apocalyptic number.

30881999 is a deficient number, since it is larger than the sum of its proper divisors (1).

30881999 is an equidigital number, since it uses as much as digits as its factorization.

30881999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 30881999 is about 5557.1574568299. The cubic root of 30881999 is about 313.7389712689.

The spelling of 30881999 in words is "thirty million, eight hundred eighty-one thousand, nine hundred ninety-nine".