21825351 has 6 divisors (see below), whose sum is σ = 31525520. Its totient is φ = 14550228.

The previous prime is 21825341. The next prime is 21825359. The reversal of 21825351 is 15352812.

It is a happy number.

It is not a de Polignac number, because 21825351 - 2⁹ = 21824839 is a prime.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21825359) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1212511 + ... + 1212528.

Almost surely, 2^21825351 is an apocalyptic number.

21825351 is a deficient number, since it is larger than the sum of its proper divisors (9700169).

21825351 is a wasteful number, since it uses less digits than its factorization.

21825351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2425045 (or 2425042 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 21825351 is about 4671.7610170042. The cubic root of 21825351 is about 279.4604874791.

The spelling of 21825351 in words is "twenty-one million, eight hundred twenty-five thousand, three hundred fifty-one".