21930783 has 24 divisors (see below), whose sum is σ = 34235568. Its totient is φ = 12450816.

The previous prime is 21930743. The next prime is 21930791. The reversal of 21930783 is 38703912.

It is not a de Polignac number, because 21930783 - 2¹⁰ = 21929759 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21930743) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27985 + ... + 28757.

It is an arithmetic number, because the mean of its divisors is an integer number (1426482).

Almost surely, 2^21930783 is an apocalyptic number.

21930783 is a deficient number, since it is larger than the sum of its proper divisors (12304785).

21930783 is a wasteful number, since it uses less digits than its factorization.

21930783 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 983 (or 976 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 21930783 is about 4683.0313900293. The cubic root of 21930783 is about 279.9097625884.

The spelling of 21930783 in words is "twenty-one million, nine hundred thirty thousand, seven hundred eighty-three".