20825261 has 4 divisors (see below), whose sum is σ = 21027552. Its totient is φ = 20622972.

The previous prime is 20825257. The next prime is 20825267. The reversal of 20825261 is 16252802.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16252802 = 2 ⋅8126401.

It is a cyclic number.

It is not a de Polignac number, because 20825261 - 2² = 20825257 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20825261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20825267) 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, 100991 + ... + 101196.

It is an arithmetic number, because the mean of its divisors is an integer number (5256888).

Almost surely, 2^20825261 is an apocalyptic number.

It is an amenable number.

20825261 is a deficient number, since it is larger than the sum of its proper divisors (202291).

20825261 is a wasteful number, since it uses less digits than its factorization.

20825261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202290.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20825261 is about 4563.4702803897. The cubic root of 20825261 is about 275.1250604736.

The spelling of 20825261 in words is "twenty million, eight hundred twenty-five thousand, two hundred sixty-one".