30630991 has 4 divisors (see below), whose sum is σ = 32432832. Its totient is φ = 28829152.

The previous prime is 30630961. The next prime is 30631001. The reversal of 30630991 is 19903603.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 30630991 - 2⁵ = 30630959 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30630911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 900895 + ... + 900928.

It is an arithmetic number, because the mean of its divisors is an integer number (8108208).

Almost surely, 2^30630991 is an apocalyptic number.

30630991 is a deficient number, since it is larger than the sum of its proper divisors (1801841).

30630991 is a wasteful number, since it uses less digits than its factorization.

30630991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1801840.

The product of its (nonzero) digits is 4374, while the sum is 31.

The square root of 30630991 is about 5534.5271704094. The cubic root of 30630991 is about 312.8866373863.

The spelling of 30630991 in words is "thirty million, six hundred thirty thousand, nine hundred ninety-one".