20513331 has 28 divisors (see below), whose sum is σ = 32396520. Its totient is φ = 12947040.

The previous prime is 20513327. The next prime is 20513341. The reversal of 20513331 is 13331502.

It is not a de Polignac number, because 20513331 - 2² = 20513327 is a prime.

It is a super-2 number, since 2×20513331² = 841593497431122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20513341) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 13111 + ... + 14591.

Almost surely, 2^20513331 is an apocalyptic number.

20513331 is a deficient number, since it is larger than the sum of its proper divisors (11883189).

20513331 is an equidigital number, since it uses as much as digits as its factorization.

20513331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1518 (or 1503 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 18.

The square root of 20513331 is about 4529.1644924864. The cubic root of 20513331 is about 273.7444960425.

Adding to 20513331 its reverse (13331502), we get a palindrome (33844833).

The spelling of 20513331 in words is "twenty million, five hundred thirteen thousand, three hundred thirty-one".