21995673 has 16 divisors (see below), whose sum is σ = 35281920. Its totient is φ = 11907216.

The previous prime is 21995621. The next prime is 21995681. The reversal of 21995673 is 37659912.

It is not a de Polignac number, because 21995673 - 2¹² = 21991577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21995473) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27165 + ... + 27962.

It is an arithmetic number, because the mean of its divisors is an integer number (2205120).

Almost surely, 2^21995673 is an apocalyptic number.

It is an amenable number.

21995673 is a deficient number, since it is larger than the sum of its proper divisors (13286247).

21995673 is a wasteful number, since it uses less digits than its factorization.

21995673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55156.

The product of its digits is 102060, while the sum is 42.

The square root of 21995673 is about 4689.9544773910. The cubic root of 21995673 is about 280.1855615214.

The spelling of 21995673 in words is "twenty-one million, nine hundred ninety-five thousand, six hundred seventy-three".