21873933 has 12 divisors (see below), whose sum is σ = 31671900. Its totient is φ = 14547456.

The previous prime is 21873931. The next prime is 21873937. The reversal of 21873933 is 33937812.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 8892324 + 12981609 = 2982^2 + 3603^2 .

It is not a de Polignac number, because 21873933 - 2¹ = 21873931 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21873931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1335 + ... + 6747.

It is an arithmetic number, because the mean of its divisors is an integer number (2639325).

Almost surely, 2^21873933 is an apocalyptic number.

It is an amenable number.

21873933 is a deficient number, since it is larger than the sum of its proper divisors (9797967).

21873933 is a wasteful number, since it uses less digits than its factorization.

21873933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5868 (or 5865 counting only the distinct ones).

The product of its digits is 27216, while the sum is 36.

The square root of 21873933 is about 4676.9576649784. The cubic root of 21873933 is about 279.6676882422.

The spelling of 21873933 in words is "twenty-one million, eight hundred seventy-three thousand, nine hundred thirty-three".