20513512 has 16 divisors (see below), whose sum is σ = 38605860. Its totient is φ = 10218624.

The previous prime is 20513461. The next prime is 20513513. The reversal of 20513512 is 21531502.

It can be written as a sum of positive squares in 2 ways, for example, as 16695396 + 3818116 = 4086^2 + 1954^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20513512.

It is not an unprimeable number, because it can be changed into a prime (20513513) 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, 2413 + ... + 6844.

Almost surely, 2^20513512 is an apocalyptic number.

It is an amenable number.

20513512 is a deficient number, since it is larger than the sum of its proper divisors (18092348).

20513512 is a wasteful number, since it uses less digits than its factorization.

20513512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9540 (or 9536 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 20513512 is about 4529.1844740527. The cubic root of 20513512 is about 273.7453011711.

It can be divided in two parts, 20513 and 512, that added together give a square (21025 = 145²).

The spelling of 20513512 in words is "twenty million, five hundred thirteen thousand, five hundred twelve".