21698930 has 48 divisors (see below), whose sum is σ = 43666560. Its totient is φ = 7756320.

The previous prime is 21698927. The next prime is 21698933. The reversal of 21698930 is 3989612.

It is an interprime number because it is at equal distance from previous prime (21698927) and next prime (21698933).

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21698933) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 95477 + ... + 95703.

It is an arithmetic number, because the mean of its divisors is an integer number (909720).

Almost surely, 2^21698930 is an apocalyptic number.

21698930 is an abundant number, since it is smaller than the sum of its proper divisors (21967630).

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

21698930 is a wasteful number, since it uses less digits than its factorization.

21698930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335 (or 324 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 21698930 is about 4658.2110299985. The cubic root of 21698930 is about 278.9198606777.

The spelling of 21698930 in words is "twenty-one million, six hundred ninety-eight thousand, nine hundred thirty".