21690622 has 4 divisors (see below), whose sum is σ = 32535936. Its totient is φ = 10845310.

The previous prime is 21690611. The next prime is 21690629. The reversal of 21690622 is 22609612.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21690629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5422654 + ... + 5422657.

It is an arithmetic number, because the mean of its divisors is an integer number (8133984).

Almost surely, 2^21690622 is an apocalyptic number.

21690622 is a deficient number, since it is larger than the sum of its proper divisors (10845314).

21690622 is a wasteful number, since it uses less digits than its factorization.

21690622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10845313.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 21690622 is about 4657.3191859695. The cubic root of 21690622 is about 278.8842588914.

The spelling of 21690622 in words is "twenty-one million, six hundred ninety thousand, six hundred twenty-two".