20949825 has 24 divisors (see below), whose sum is σ = 37303168. Its totient is φ = 10313280.

The previous prime is 20949823. The next prime is 20949829. The reversal of 20949825 is 52894902.

It is not a de Polignac number, because 20949825 - 2¹ = 20949823 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20949823) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9769 + ... + 11718.

Almost surely, 2^20949825 is an apocalyptic number.

20949825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20949825 is a deficient number, since it is larger than the sum of its proper divisors (16353343).

20949825 is a wasteful number, since it uses less digits than its factorization.

20949825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21513 (or 21508 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 39.

The square root of 20949825 is about 4577.0978796613. The cubic root of 20949825 is about 275.6725138033.

The spelling of 20949825 in words is "twenty million, nine hundred forty-nine thousand, eight hundred twenty-five".