21348090 has 64 divisors (see below), whose sum is σ = 60289920. Its totient is φ = 5356800.

The previous prime is 21348083. The next prime is 21348097. The reversal of 21348090 is 9084312.

It is an interprime number because it is at equal distance from previous prime (21348083) and next prime (21348097).

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 (21348097) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2265 + ... + 6915.

It is an arithmetic number, because the mean of its divisors is an integer number (942030).

Almost surely, 2^21348090 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21348090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30144960).

21348090 is an abundant number, since it is smaller than the sum of its proper divisors (38941830).

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

21348090 is a wasteful number, since it uses less digits than its factorization.

21348090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4684 (or 4678 counting only the distinct ones).

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

The square root of 21348090 is about 4620.3993333910. The cubic root of 21348090 is about 277.4084431337.

The spelling of 21348090 in words is "twenty-one million, three hundred forty-eight thousand, ninety".