20631057 has 8 divisors (see below), whose sum is σ = 27530784. Its totient is φ = 13742688.

The previous prime is 20631043. The next prime is 20631097. The reversal of 20631057 is 75013602.

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

It is not a de Polignac number, because 20631057 - 2¹⁰ = 20630033 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20631097) 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, 3298 + ... + 7220.

It is an arithmetic number, because the mean of its divisors is an integer number (3441348).

Almost surely, 2^20631057 is an apocalyptic number.

It is an amenable number.

20631057 is a deficient number, since it is larger than the sum of its proper divisors (6899727).

20631057 is a wasteful number, since it uses less digits than its factorization.

20631057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5679.

The product of its (nonzero) digits is 1260, while the sum is 24.

The square root of 20631057 is about 4542.1423359468. The cubic root of 20631057 is about 274.2671706291.

Adding to 20631057 its reverse (75013602), we get a palindrome (95644659).

The spelling of 20631057 in words is "twenty million, six hundred thirty-one thousand, fifty-seven".