21951963 has 12 divisors (see below), whose sum is σ = 34591128. Its totient is φ = 13304160.

The previous prime is 21951931. The next prime is 21951971. The reversal of 21951963 is 36915912.

It is not a de Polignac number, because 21951963 - 2⁵ = 21951931 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21951263) 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 11 ways as a sum of consecutive naturals, for example, 110770 + ... + 110967.

It is an arithmetic number, because the mean of its divisors is an integer number (2882594).

Almost surely, 2^21951963 is an apocalyptic number.

21951963 is a deficient number, since it is larger than the sum of its proper divisors (12639165).

21951963 is a wasteful number, since it uses less digits than its factorization.

21951963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221754 (or 221751 counting only the distinct ones).

The product of its digits is 14580, while the sum is 36.

The square root of 21951963 is about 4685.2922000661. The cubic root of 21951963 is about 279.9998426870. Note that the first 3 decimals are identical.

The spelling of 21951963 in words is "twenty-one million, nine hundred fifty-one thousand, nine hundred sixty-three".