20690157 has 8 divisors (see below), whose sum is σ = 27919584. Its totient is φ = 13627088.

The previous prime is 20690149. The next prime is 20690161. The reversal of 20690157 is 75109602.

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 20690157 - 2³ = 20690149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20690147) 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, 41298 + ... + 41795.

It is an arithmetic number, because the mean of its divisors is an integer number (3489948).

Almost surely, 2^20690157 is an apocalyptic number.

It is an amenable number.

20690157 is a deficient number, since it is larger than the sum of its proper divisors (7229427).

20690157 is an equidigital number, since it uses as much as digits as its factorization.

20690157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83179.

The product of its (nonzero) digits is 3780, while the sum is 30.

The square root of 20690157 is about 4548.6434241431. The cubic root of 20690157 is about 274.5288107490.

Adding to 20690157 its reverse (75109602), we get a palindrome (95799759).

The spelling of 20690157 in words is "twenty million, six hundred ninety thousand, one hundred fifty-seven".