21980430 has 32 divisors (see below), whose sum is σ = 58615200. Its totient is φ = 5861376.

The previous prime is 21980429. The next prime is 21980437. The reversal of 21980430 is 3408912.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21980394 and 21980403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21980437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40435 + ... + 40974.

It is an arithmetic number, because the mean of its divisors is an integer number (1831725).

Almost surely, 2^21980430 is an apocalyptic number.

21980430 is an abundant number, since it is smaller than the sum of its proper divisors (36634770).

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

21980430 is a wasteful number, since it uses less digits than its factorization.

21980430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81425 (or 81419 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21980430 is about 4688.3291266719. The cubic root of 21980430 is about 280.1208237058.

The spelling of 21980430 in words is "twenty-one million, nine hundred eighty thousand, four hundred thirty".