21090348 has 24 divisors (see below), whose sum is σ = 54678960. Its totient is φ = 7030080.

The previous prime is 21090347. The next prime is 21090367. The reversal of 21090348 is 84309012.

It is a super-2 number, since 2×21090348² = 889605557522208, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21090341) 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, 97533 + ... + 97748.

It is an arithmetic number, because the mean of its divisors is an integer number (2278290).

Almost surely, 2^21090348 is an apocalyptic number.

It is an amenable number.

21090348 is an abundant number, since it is smaller than the sum of its proper divisors (33588612).

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

21090348 is a wasteful number, since it uses less digits than its factorization.

21090348 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195294 (or 195286 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21090348 is about 4592.4228899351. The cubic root of 21090348 is about 276.2875075844.

The spelling of 21090348 in words is "twenty-one million, ninety thousand, three hundred forty-eight".