21963138 has 8 divisors (see below), whose sum is σ = 43926288. Its totient is φ = 7321044.

The previous prime is 21963127. The next prime is 21963143. The reversal of 21963138 is 83136912.

It is a sphenic number, since it is the product of 3 distinct primes.

21963138 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21963099 and 21963108.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1830256 + ... + 1830267.

It is an arithmetic number, because the mean of its divisors is an integer number (5490786).

Almost surely, 2^21963138 is an apocalyptic number.

21963138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21963138 is a wasteful number, since it uses less digits than its factorization.

21963138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3660528.

The product of its digits is 7776, while the sum is 33.

The square root of 21963138 is about 4686.4846100249. The cubic root of 21963138 is about 280.0473474354.

The spelling of 21963138 in words is "twenty-one million, nine hundred sixty-three thousand, one hundred thirty-eight".