21623722 has 8 divisors (see below), whose sum is σ = 32846400. Its totient is φ = 10674924.

The previous prime is 21623699. The next prime is 21623731. The reversal of 21623722 is 22732612.

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

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, 68272 + ... + 68587.

It is an arithmetic number, because the mean of its divisors is an integer number (4105800).

Almost surely, 2^21623722 is an apocalyptic number.

21623722 is a deficient number, since it is larger than the sum of its proper divisors (11222678).

21623722 is a wasteful number, since it uses less digits than its factorization.

21623722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136940.

The product of its digits is 2016, while the sum is 25.

The square root of 21623722 is about 4650.1313959930. The cubic root of 21623722 is about 278.5972443562.

The spelling of 21623722 in words is "twenty-one million, six hundred twenty-three thousand, seven hundred twenty-two".