30706640 has 20 divisors (see below), whose sum is σ = 71393124. Its totient is φ = 12282624.

The previous prime is 30706631. The next prime is 30706657. The reversal of 30706640 is 4660703.

It can be written as a sum of positive squares in 2 ways, for example, as 5345344 + 25361296 = 2312^2 + 5036^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 191837 + ... + 191996.

Almost surely, 2^30706640 is an apocalyptic number.

It is an amenable number.

30706640 is an abundant number, since it is smaller than the sum of its proper divisors (40686484).

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

30706640 is a wasteful number, since it uses less digits than its factorization.

30706640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383846 (or 383840 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 30706640 is about 5541.3572344688. The cubic root of 30706640 is about 313.1440031203.

The spelling of 30706640 in words is "thirty million, seven hundred six thousand, six hundred forty".