21049406 has 8 divisors (see below), whose sum is σ = 36084720. Its totient is φ = 9021168.

The previous prime is 21049387. The next prime is 21049493. The reversal of 21049406 is 60494012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 751751 + ... + 751778.

It is an arithmetic number, because the mean of its divisors is an integer number (4510590).

Almost surely, 2^21049406 is an apocalyptic number.

21049406 is a deficient number, since it is larger than the sum of its proper divisors (15035314).

21049406 is a wasteful number, since it uses less digits than its factorization.

21049406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1503538.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 21049406 is about 4587.9631646298. The cubic root of 21049406 is about 276.1086091493.

The spelling of 21049406 in words is "twenty-one million, forty-nine thousand, four hundred six".