21000790 has 8 divisors (see below), whose sum is σ = 37801440. Its totient is φ = 8400312.

The previous prime is 21000779. The next prime is 21000803. The reversal of 21000790 is 9700012.

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, 1050030 + ... + 1050049.

It is an arithmetic number, because the mean of its divisors is an integer number (4725180).

Almost surely, 2^21000790 is an apocalyptic number.

21000790 is a deficient number, since it is larger than the sum of its proper divisors (16800650).

21000790 is a wasteful number, since it uses less digits than its factorization.

21000790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2100086.

The product of its (nonzero) digits is 126, while the sum is 19.

The square root of 21000790 is about 4582.6618902118. The cubic root of 21000790 is about 275.8958771981.

The spelling of 21000790 in words is "twenty-one million, seven hundred ninety", and thus it is an aban number.