20699057 has 8 divisors (see below), whose sum is σ = 21715584. Its totient is φ = 19692288.

The previous prime is 20699053. The next prime is 20699059. The reversal of 20699057 is 75099602.

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

It is a cyclic number.

It is not a de Polignac number, because 20699057 - 2² = 20699053 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20699057.

It is not an unprimeable number, because it can be changed into a prime (20699051) 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, 2108 + ... + 6770.

It is an arithmetic number, because the mean of its divisors is an integer number (2714448).

Almost surely, 2^20699057 is an apocalyptic number.

It is an amenable number.

20699057 is a deficient number, since it is larger than the sum of its proper divisors (1016527).

20699057 is a wasteful number, since it uses less digits than its factorization.

20699057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4879.

The product of its (nonzero) digits is 34020, while the sum is 38.

The square root of 20699057 is about 4549.6216326196. The cubic root of 20699057 is about 274.5681685326.

The spelling of 20699057 in words is "twenty million, six hundred ninety-nine thousand, fifty-seven".