21101408 has 12 divisors (see below), whose sum is σ = 41543460. Its totient is φ = 10550688.

The previous prime is 21101407. The next prime is 21101411. The reversal of 21101408 is 80410112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 329678 + ... + 329741.

It is an arithmetic number, because the mean of its divisors is an integer number (3461955).

Almost surely, 2^21101408 is an apocalyptic number.

It is an amenable number.

21101408 is a deficient number, since it is larger than the sum of its proper divisors (20442052).

21101408 is an equidigital number, since it uses as much as digits as its factorization.

21101408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659429 (or 659421 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 21101408 is about 4593.6268895068. The cubic root of 21101408 is about 276.3357951681.

The spelling of 21101408 in words is "twenty-one million, one hundred one thousand, four hundred eight".