20660157 has 16 divisors (see below), whose sum is σ = 34980480. Its totient is φ = 11805696.

The previous prime is 20660153. The next prime is 20660161. The reversal of 20660157 is 75106602.

20660157 is a `hidden beast` number, since 2 + 0 + 6 + 601 + 57 = 666.

It is an interprime number because it is at equal distance from previous prime (20660153) and next prime (20660161).

It is not a de Polignac number, because 20660157 - 2² = 20660153 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 20660157.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20660153) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54468 + ... + 54845.

It is an arithmetic number, because the mean of its divisors is an integer number (2186280).

Almost surely, 2^20660157 is an apocalyptic number.

20660157 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20660157 is a deficient number, since it is larger than the sum of its proper divisors (14320323).

20660157 is a wasteful number, since it uses less digits than its factorization.

20660157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109329 (or 109323 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 20660157 is about 4545.3445413962. The cubic root of 20660157 is about 274.3960608605.

Adding to 20660157 its reverse (75106602), we get a palindrome (95766759).

The spelling of 20660157 in words is "twenty million, six hundred sixty thousand, one hundred fifty-seven".