21782925 has 60 divisors (see below), whose sum is σ = 41771136. Its totient is φ = 11210400.

The previous prime is 21782923. The next prime is 21782941. The reversal of 21782925 is 52928712.

It is not a de Polignac number, because 21782925 - 2¹ = 21782923 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21782925.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21782923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 62602 + ... + 62948.

Almost surely, 2^21782925 is an apocalyptic number.

21782925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21782925 is a deficient number, since it is larger than the sum of its proper divisors (19988211).

21782925 is a wasteful number, since it uses less digits than its factorization.

21782925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400 (or 386 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 21782925 is about 4667.2181221794. The cubic root of 21782925 is about 279.2792902184.

The spelling of 21782925 in words is "twenty-one million, seven hundred eighty-two thousand, nine hundred twenty-five".