20657998 has 8 divisors (see below), whose sum is σ = 31006800. Its totient is φ = 10322400.

The previous prime is 20657983. The next prime is 20657999. The reversal of 20657998 is 89975602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20657999) 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, 3078 + ... + 7126.

It is an arithmetic number, because the mean of its divisors is an integer number (3875850).

Almost surely, 2^20657998 is an apocalyptic number.

20657998 is a deficient number, since it is larger than the sum of its proper divisors (10348802).

20657998 is a wasteful number, since it uses less digits than its factorization.

20657998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6602.

The product of its (nonzero) digits is 272160, while the sum is 46.

The square root of 20657998 is about 4545.1070394436. The cubic root of 20657998 is about 274.3865023379.

The spelling of 20657998 in words is "twenty million, six hundred fifty-seven thousand, nine hundred ninety-eight".