21213962 has 36 divisors (see below), whose sum is σ = 40709970. Its totient is φ = 8260560.

The previous prime is 21213947. The next prime is 21213971. The reversal of 21213962 is 26931212.

It can be written as a sum of positive squares in only one way, i.e., 13097161 + 8116801 = 3619^2 + 2849^2 .

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 10964 + ... + 12752.

Almost surely, 2^21213962 is an apocalyptic number.

21213962 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21213962 is a deficient number, since it is larger than the sum of its proper divisors (19496008).

21213962 is a wasteful number, since it uses less digits than its factorization.

21213962 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1827 (or 1809 counting only the distinct ones).

The product of its digits is 1296, while the sum is 26.

The square root of 21213962 is about 4605.8617000514. The cubic root of 21213962 is about 276.8262452561.

The spelling of 21213962 in words is "twenty-one million, two hundred thirteen thousand, nine hundred sixty-two".