21819698 has 8 divisors (see below), whose sum is σ = 32750892. Its totient is φ = 10902736.

The previous prime is 21819683. The next prime is 21819713. The reversal of 21819698 is 89691812.

It is an interprime number because it is at equal distance from previous prime (21819683) and next prime (21819713).

It can be written as a sum of positive squares in 2 ways, for example, as 21780889 + 38809 = 4667^2 + 197^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21819698² = 952198441622408, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2036 + ... + 6912.

Almost surely, 2^21819698 is an apocalyptic number.

21819698 is a deficient number, since it is larger than the sum of its proper divisors (10931194).

21819698 is a wasteful number, since it uses less digits than its factorization.

21819698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7116.

The product of its digits is 62208, while the sum is 44.

The square root of 21819698 is about 4671.1559597170. The cubic root of 21819698 is about 279.4363576411.

The spelling of 21819698 in words is "twenty-one million, eight hundred nineteen thousand, six hundred ninety-eight".