21986270 has 32 divisors (see below), whose sum is σ = 42143328. Its totient is φ = 8229888.

The previous prime is 21986269. The next prime is 21986273. The reversal of 21986270 is 7268912.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21986270.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21986273) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47882 + ... + 48338.

It is an arithmetic number, because the mean of its divisors is an integer number (1316979).

Almost surely, 2^21986270 is an apocalyptic number.

21986270 is a deficient number, since it is larger than the sum of its proper divisors (20157058).

21986270 is a wasteful number, since it uses less digits than its factorization.

21986270 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 764.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 21986270 is about 4688.9519084759. The cubic root of 21986270 is about 280.1456300260.

The spelling of 21986270 in words is "twenty-one million, nine hundred eighty-six thousand, two hundred seventy".