21748370 has 32 divisors (see below), whose sum is σ = 45214848. Its totient is φ = 7377408.

The previous prime is 21748367. The next prime is 21748399. The reversal of 21748370 is 7384712.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5189 + ... + 8391.

It is an arithmetic number, because the mean of its divisors is an integer number (1412964).

Almost surely, 2^21748370 is an apocalyptic number.

21748370 is an abundant number, since it is smaller than the sum of its proper divisors (23466478).

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

21748370 is a wasteful number, since it uses less digits than its factorization.

21748370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3314.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 21748370 is about 4663.5147689270. The cubic root of 21748370 is about 279.1315352935.

The spelling of 21748370 in words is "twenty-one million, seven hundred forty-eight thousand, three hundred seventy".