21942634 has 32 divisors (see below), whose sum is σ = 38678400. Its totient is φ = 9142848.

The previous prime is 21942629. The next prime is 21942649. The reversal of 21942634 is 43624912.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21942596 and 21942605.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139684 + ... + 139840.

It is an arithmetic number, because the mean of its divisors is an integer number (1208700).

Almost surely, 2^21942634 is an apocalyptic number.

21942634 is a deficient number, since it is larger than the sum of its proper divisors (16735766).

21942634 is a wasteful number, since it uses less digits than its factorization.

21942634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382.

The product of its digits is 10368, while the sum is 31.

The square root of 21942634 is about 4684.2965320313. The cubic root of 21942634 is about 279.9601729067.

The spelling of 21942634 in words is "twenty-one million, nine hundred forty-two thousand, six hundred thirty-four".