30909640 has 32 divisors (see below), whose sum is σ = 69783480. Its totient is φ = 12321792.

The previous prime is 30909629. The next prime is 30909649. The reversal of 30909640 is 4690903.

It can be written as a sum of positive squares in 4 ways, for example, as 18335524 + 12574116 = 4282^2 + 3546^2 .

It is not an unprimeable number, because it can be changed into a prime (30909649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12334 + ... + 14626.

Almost surely, 2^30909640 is an apocalyptic number.

It is an amenable number.

30909640 is an abundant number, since it is smaller than the sum of its proper divisors (38873840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

30909640 is a wasteful number, since it uses less digits than its factorization.

30909640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2641 (or 2637 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 30909640 is about 5559.6438734869. The cubic root of 30909640 is about 313.8325476041.

It can be divided in two parts, 309096 and 40, that added together give a square (309136 = 556²).

The spelling of 30909640 in words is "thirty million, nine hundred nine thousand, six hundred forty".