20507057 has 4 divisors (see below), whose sum is σ = 20766720. Its totient is φ = 20247396.

The previous prime is 20507051. The next prime is 20507107. The reversal of 20507057 is 75070502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20507057 - 2¹² = 20502961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20507051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 129713 + ... + 129870.

It is an arithmetic number, because the mean of its divisors is an integer number (5191680).

Almost surely, 2^20507057 is an apocalyptic number.

It is an amenable number.

20507057 is a deficient number, since it is larger than the sum of its proper divisors (259663).

20507057 is an equidigital number, since it uses as much as digits as its factorization.

20507057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259662.

The product of its (nonzero) digits is 2450, while the sum is 26.

The square root of 20507057 is about 4528.4718172911. The cubic root of 20507057 is about 273.7165849555.

Adding to 20507057 its reverse (75070502), we get a palindrome (95577559).

The spelling of 20507057 in words is "twenty million, five hundred seven thousand, fifty-seven".