21377930 has 32 divisors (see below), whose sum is σ = 45498240. Its totient is φ = 7076160.

The previous prime is 21377929. The next prime is 21377947. The reversal of 21377930 is 3977312.

It is a Curzon 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 15 ways as a sum of consecutive naturals, for example, 3236 + ... + 7295.

It is an arithmetic number, because the mean of its divisors is an integer number (1421820).

Almost surely, 2^21377930 is an apocalyptic number.

21377930 is an abundant number, since it is smaller than the sum of its proper divisors (24120310).

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

21377930 is a wasteful number, since it uses less digits than its factorization.

21377930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10574.

The product of its (nonzero) digits is 7938, while the sum is 32.

The square root of 21377930 is about 4623.6273638778. The cubic root of 21377930 is about 277.5376352386.

The spelling of 21377930 in words is "twenty-one million, three hundred seventy-seven thousand, nine hundred thirty".