21213631201 has 9 divisors (see below), whose sum is σ = 24678267249. Its totient is φ = 18182238564.

The previous prime is 21213631181. The next prime is 21213631217. The reversal of 21213631201 is 10213631212.

It is a happy number.

The square root of 21213631201 is 145649.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 21213631201 - 2¹⁵ = 21213598433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213631261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1009140 + ... + 1029946.

Almost surely, 2^21213631201 is an apocalyptic number.

21213631201 is the 145649-th square number.

21213631201 is the 72825-th centered octagonal number.

It is an amenable number.

21213631201 is a deficient number, since it is larger than the sum of its proper divisors (3464636048).

21213631201 is an frugal number, since it uses more digits than its factorization.

21213631201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41628 (or 20814 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The spelling of 21213631201 in words is "twenty-one billion, two hundred thirteen million, six hundred thirty-one thousand, two hundred one".