21831201 has 40 divisors (see below), whose sum is σ = 37674560. Its totient is φ = 12340512.

The previous prime is 21831181. The next prime is 21831217. The reversal of 21831201 is 10213812.

It is not a de Polignac number, because 21831201 - 2⁹ = 21830689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21831001) 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 39 ways as a sum of consecutive naturals, for example, 78675 + ... + 78951.

It is an arithmetic number, because the mean of its divisors is an integer number (941864).

Almost surely, 2^21831201 is an apocalyptic number.

21831201 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21831201 is a deficient number, since it is larger than the sum of its proper divisors (15843359).

21831201 is a wasteful number, since it uses less digits than its factorization.

21831201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435 (or 426 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 21831201 is about 4672.3870772872. The cubic root of 21831201 is about 279.4854538253.

The spelling of 21831201 in words is "twenty-one million, eight hundred thirty-one thousand, two hundred one".