21678675 has 12 divisors (see below), whose sum is σ = 35842200. Its totient is φ = 11561920.

The previous prime is 21678667. The next prime is 21678697. The reversal of 21678675 is 57687612.

It is not a de Polignac number, because 21678675 - 2³ = 21678667 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 144450 + ... + 144599.

It is an arithmetic number, because the mean of its divisors is an integer number (2986850).

Almost surely, 2^21678675 is an apocalyptic number.

21678675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21678675 is a deficient number, since it is larger than the sum of its proper divisors (14163525).

21678675 is a wasteful number, since it uses less digits than its factorization.

21678675 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289062 (or 289057 counting only the distinct ones).

The product of its digits is 141120, while the sum is 42.

The square root of 21678675 is about 4656.0364044969. The cubic root of 21678675 is about 278.8330471720.

The spelling of 21678675 in words is "twenty-one million, six hundred seventy-eight thousand, six hundred seventy-five".