20504051 has 4 divisors (see below), whose sum is σ = 21165504. Its totient is φ = 19842600.

The previous prime is 20504009. The next prime is 20504053. The reversal of 20504051 is 15040502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20504051 - 2¹⁰ = 20503027 is a prime.

It is a super-2 number, since 2×20504051² = 840832214821202, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20504053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 330680 + ... + 330741.

It is an arithmetic number, because the mean of its divisors is an integer number (5291376).

Almost surely, 2^20504051 is an apocalyptic number.

20504051 is a deficient number, since it is larger than the sum of its proper divisors (661453).

20504051 is an equidigital number, since it uses as much as digits as its factorization.

20504051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661452.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 20504051 is about 4528.1399050824. The cubic root of 20504051 is about 273.7032101734.

Adding to 20504051 its reverse (15040502), we get a palindrome (35544553).

The spelling of 20504051 in words is "twenty million, five hundred four thousand, fifty-one".