21377430 has 48 divisors (see below), whose sum is σ = 55851120. Its totient is φ = 5673024.

The previous prime is 21377417. The next prime is 21377459. The reversal of 21377430 is 3477312.

It is a junction number, because it is equal to n+sod(n) for n = 21377394 and 21377403.

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 23 ways as a sum of consecutive naturals, for example, 23769 + ... + 24651.

It is an arithmetic number, because the mean of its divisors is an integer number (1163565).

Almost surely, 2^21377430 is an apocalyptic number.

21377430 is an abundant number, since it is smaller than the sum of its proper divisors (34473690).

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

21377430 is a wasteful number, since it uses less digits than its factorization.

21377430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1165 (or 1162 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 27.

The square root of 21377430 is about 4623.5732934604. The cubic root of 21377430 is about 277.5354714822.

The spelling of 21377430 in words is "twenty-one million, three hundred seventy-seven thousand, four hundred thirty".