21748995 has 24 divisors (see below), whose sum is σ = 37814400. Its totient is φ = 11563776.

The previous prime is 21748981. The next prime is 21748999. The reversal of 21748995 is 59984712.

It is not a de Polignac number, because 21748995 - 2⁶ = 21748931 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 21748995.

It is not an unprimeable number, because it can be changed into a prime (21748999) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 21051 + ... + 22059.

It is an arithmetic number, because the mean of its divisors is an integer number (1575600).

Almost surely, 2^21748995 is an apocalyptic number.

21748995 is a deficient number, since it is larger than the sum of its proper divisors (16065405).

21748995 is a wasteful number, since it uses less digits than its factorization.

21748995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1499 (or 1496 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 21748995 is about 4663.5817779900. The cubic root of 21748995 is about 279.1342091420.

The spelling of 21748995 in words is "twenty-one million, seven hundred forty-eight thousand, nine hundred ninety-five".