21889478 has 16 divisors (see below), whose sum is σ = 35810880. Its totient is φ = 9974016.

The previous prime is 21889453. The next prime is 21889487. The reversal of 21889478 is 87498812.

It is a super-2 number, since 2×21889478² = 958298494224968, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3275 + ... + 7382.

It is an arithmetic number, because the mean of its divisors is an integer number (2238180).

Almost surely, 2^21889478 is an apocalyptic number.

21889478 is a deficient number, since it is larger than the sum of its proper divisors (13921402).

21889478 is a wasteful number, since it uses less digits than its factorization.

21889478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10751.

The product of its digits is 258048, while the sum is 47.

The square root of 21889478 is about 4678.6192407590. The cubic root of 21889478 is about 279.7339224027.

The spelling of 21889478 in words is "twenty-one million, eight hundred eighty-nine thousand, four hundred seventy-eight".