20625511 has 4 divisors (see below), whose sum is σ = 20658232. Its totient is φ = 20592792.

The previous prime is 20625499. The next prime is 20625529. The reversal of 20625511 is 11552602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11552602 = 2 ⋅5776301.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20625511 is a prime.

It is a super-2 number, since 2×20625511² = 850823408022242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20625541) 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, 15396 + ... + 16681.

It is an arithmetic number, because the mean of its divisors is an integer number (5164558).

Almost surely, 2^20625511 is an apocalyptic number.

20625511 is a deficient number, since it is larger than the sum of its proper divisors (32721).

20625511 is an equidigital number, since it uses as much as digits as its factorization.

20625511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32720.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 20625511 is about 4541.5317900462. The cubic root of 20625511 is about 274.2425924402.

The spelling of 20625511 in words is "twenty million, six hundred twenty-five thousand, five hundred eleven".