21938445 has 40 divisors (see below), whose sum is σ = 41411040. Its totient is φ = 11080800.

The previous prime is 21938437. The next prime is 21938453. The reversal of 21938445 is 54483912.

It is an interprime number because it is at equal distance from previous prime (21938437) and next prime (21938453).

It is not a de Polignac number, because 21938445 - 2³ = 21938437 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 6270 + ... + 9120.

It is an arithmetic number, because the mean of its divisors is an integer number (1035276).

Almost surely, 2^21938445 is an apocalyptic number.

It is an amenable number.

21938445 is a deficient number, since it is larger than the sum of its proper divisors (19472595).

21938445 is a wasteful number, since it uses less digits than its factorization.

21938445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2887 (or 2878 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 21938445 is about 4683.8493784493. The cubic root of 21938445 is about 279.9423563310.

The spelling of 21938445 in words is "twenty-one million, nine hundred thirty-eight thousand, four hundred forty-five".