20728670 has 16 divisors (see below), whose sum is σ = 37387440. Its totient is φ = 8274624.

The previous prime is 20728637. The next prime is 20728691. The reversal of 20728670 is 7682702.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3869 + ... + 7511.

It is an arithmetic number, because the mean of its divisors is an integer number (2336715).

Almost surely, 2^20728670 is an apocalyptic number.

20728670 is a deficient number, since it is larger than the sum of its proper divisors (16658770).

20728670 is a wasteful number, since it uses less digits than its factorization.

20728670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4219.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 20728670 is about 4552.8749159185. The cubic root of 20728670 is about 274.6990426562.

The spelling of 20728670 in words is "twenty million, seven hundred twenty-eight thousand, six hundred seventy".