21794278 has 12 divisors (see below), whose sum is σ = 35933940. Its totient is φ = 9906380.

The previous prime is 21794261. The next prime is 21794287. The reversal of 21794278 is 87249712.

It is a self number, because there is not a number n which added to its sum of digits gives 21794278.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 44788 + ... + 45271.

It is an arithmetic number, because the mean of its divisors is an integer number (2994495).

Almost surely, 2^21794278 is an apocalyptic number.

21794278 is a deficient number, since it is larger than the sum of its proper divisors (14139662).

21794278 is a wasteful number, since it uses less digits than its factorization.

21794278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90083 (or 90072 counting only the distinct ones).

The product of its digits is 56448, while the sum is 40.

The square root of 21794278 is about 4668.4342128812. The cubic root of 21794278 is about 279.3278008004.

The spelling of 21794278 in words is "twenty-one million, seven hundred ninety-four thousand, two hundred seventy-eight".