21979848 has 32 divisors (see below), whose sum is σ = 59945760. Its totient is φ = 6660480.

The previous prime is 21979847. The next prime is 21979849. The reversal of 21979848 is 84897912.

It is an interprime number because it is at equal distance from previous prime (21979847) and next prime (21979849).

It is a super-2 number, since 2×21979848² = 966227436206208, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21979797 and 21979806.

It is not an unprimeable number, because it can be changed into a prime (21979847) 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, 41365 + ... + 41892.

It is an arithmetic number, because the mean of its divisors is an integer number (1873305).

Almost surely, 2^21979848 is an apocalyptic number.

It is an amenable number.

21979848 is an abundant number, since it is smaller than the sum of its proper divisors (37965912).

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

21979848 is a wasteful number, since it uses less digits than its factorization.

21979848 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83277 (or 83273 counting only the distinct ones).

The product of its digits is 290304, while the sum is 48.

The square root of 21979848 is about 4688.2670572398. The cubic root of 21979848 is about 280.1183513284.

The spelling of 21979848 in words is "twenty-one million, nine hundred seventy-nine thousand, eight hundred forty-eight".