21690348 has 24 divisors (see below), whose sum is σ = 50687280. Its totient is φ = 7219200.

The previous prime is 21690337. The next prime is 21690349. The reversal of 21690348 is 84309612.

It is a super-2 number, since 2×21690348² = 940942392722208, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21690349) 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, 12748 + ... + 14348.

It is an arithmetic number, because the mean of its divisors is an integer number (2111970).

Almost surely, 2^21690348 is an apocalyptic number.

It is an amenable number.

21690348 is an abundant number, since it is smaller than the sum of its proper divisors (28996932).

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

21690348 is a wasteful number, since it uses less digits than its factorization.

21690348 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2737 (or 2735 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 21690348 is about 4657.2897698125. The cubic root of 21690348 is about 278.8830845804.

The spelling of 21690348 in words is "twenty-one million, six hundred ninety thousand, three hundred forty-eight".