21087794 has 32 divisors (see below), whose sum is σ = 39325440. Its totient is φ = 8258112.

The previous prime is 21087779. The next prime is 21087809. The reversal of 21087794 is 49778012.

It is an interprime number because it is at equal distance from previous prime (21087779) and next prime (21087809).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19307 + ... + 20369.

It is an arithmetic number, because the mean of its divisors is an integer number (1228920).

Almost surely, 2^21087794 is an apocalyptic number.

21087794 is a deficient number, since it is larger than the sum of its proper divisors (18237646).

21087794 is a wasteful number, since it uses less digits than its factorization.

21087794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1194.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 21087794 is about 4592.1448147897. The cubic root of 21087794 is about 276.2763545081.

The spelling of 21087794 in words is "twenty-one million, eighty-seven thousand, seven hundred ninety-four".