21499190 has 16 divisors (see below), whose sum is σ = 39076128. Its totient is φ = 8515776.

The previous prime is 21499171. The next prime is 21499199. The reversal of 21499190 is 9199412.

It is a super-2 number, since 2×21499190² = 924430341312200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21499190.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21499199) 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, 9407 + ... + 11466.

It is an arithmetic number, because the mean of its divisors is an integer number (2442258).

Almost surely, 2^21499190 is an apocalyptic number.

21499190 is a deficient number, since it is larger than the sum of its proper divisors (17576938).

21499190 is a wasteful number, since it uses less digits than its factorization.

21499190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20983.

The product of its (nonzero) digits is 5832, while the sum is 35.

The square root of 21499190 is about 4636.7219023789. The cubic root of 21499190 is about 278.0613963045.

The spelling of 21499190 in words is "twenty-one million, four hundred ninety-nine thousand, one hundred ninety".