21889004 has 24 divisors (see below), whose sum is σ = 39197760. Its totient is φ = 10692864.

The previous prime is 21889003. The next prime is 21889019. The reversal of 21889004 is 40098812.

It is a happy number.

It is a super-2 number, since 2×21889004² = 958256992224032, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21889001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35402 + ... + 36014.

It is an arithmetic number, because the mean of its divisors is an integer number (1633240).

Almost surely, 2^21889004 is an apocalyptic number.

It is an amenable number.

21889004 is a deficient number, since it is larger than the sum of its proper divisors (17308756).

21889004 is a wasteful number, since it uses less digits than its factorization.

21889004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 809 (or 807 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 21889004 is about 4678.5685845139. The cubic root of 21889004 is about 279.7319032463.

Adding to 21889004 its sum of digits (32), we get a triangular number (21889036 = T₆₆₁₆).

The spelling of 21889004 in words is "twenty-one million, eight hundred eighty-nine thousand, four".