21169994 has 16 divisors (see below), whose sum is σ = 32735328. Its totient is φ = 10260432.

The previous prime is 21169987. The next prime is 21169997. The reversal of 21169994 is 49996112.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21169997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38429 + ... + 38975.

It is an arithmetic number, because the mean of its divisors is an integer number (2045958).

Almost surely, 2^21169994 is an apocalyptic number.

21169994 is a deficient number, since it is larger than the sum of its proper divisors (11565334).

21169994 is a wasteful number, since it uses less digits than its factorization.

21169994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1109.

The product of its digits is 34992, while the sum is 41.

The square root of 21169994 is about 4601.0861761110. The cubic root of 21169994 is about 276.6348632012.

The spelling of 21169994 in words is "twenty-one million, one hundred sixty-nine thousand, nine hundred ninety-four".