30870640 has 40 divisors (see below), whose sum is σ = 75999600. Its totient is φ = 11621376.

The previous prime is 30870613. The next prime is 30870647. The reversal of 30870640 is 4607803.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 30870599 and 30870608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30870647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9990 + ... + 12709.

It is an arithmetic number, because the mean of its divisors is an integer number (1899990).

Almost surely, 2^30870640 is an apocalyptic number.

It is an amenable number.

30870640 is an abundant number, since it is smaller than the sum of its proper divisors (45128960).

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

30870640 is a wasteful number, since it uses less digits than its factorization.

30870640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22729 (or 22723 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 30870640 is about 5556.1353475235. The cubic root of 30870640 is about 313.7005001193.

The spelling of 30870640 in words is "thirty million, eight hundred seventy thousand, six hundred forty".