21932406 has 12 divisors (see below), whose sum is σ = 47520252. Its totient is φ = 7310796.

The previous prime is 21932401. The next prime is 21932419. The reversal of 21932406 is 60423912.

It is a self number, because there is not a number n which added to its sum of digits gives 21932406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21932401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 609216 + ... + 609251.

It is an arithmetic number, because the mean of its divisors is an integer number (3960021).

Almost surely, 2^21932406 is an apocalyptic number.

21932406 is an abundant number, since it is smaller than the sum of its proper divisors (25587846).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21932406 is a wasteful number, since it uses less digits than its factorization.

21932406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1218475 (or 1218472 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 21932406 is about 4683.2046720168. The cubic root of 21932406 is about 279.9166673782.

The spelling of 21932406 in words is "twenty-one million, nine hundred thirty-two thousand, four hundred six".