21890814 has 32 divisors (see below), whose sum is σ = 48784896. Its totient is φ = 6491520.

The previous prime is 21890807. The next prime is 21890839. The reversal of 21890814 is 41809812.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

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, 427 + ... + 6630.

It is an arithmetic number, because the mean of its divisors is an integer number (1524528).

Almost surely, 2^21890814 is an apocalyptic number.

21890814 is an abundant number, since it is smaller than the sum of its proper divisors (26894082).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21890814 is a wasteful number, since it uses less digits than its factorization.

21890814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7120.

The product of its (nonzero) digits is 4608, while the sum is 33.

The square root of 21890814 is about 4678.7620157473. The cubic root of 21890814 is about 279.7396133701.

The spelling of 21890814 in words is "twenty-one million, eight hundred ninety thousand, eight hundred fourteen".