21277893 has 32 divisors (see below), whose sum is σ = 35788032. Its totient is φ = 10944000.

The previous prime is 21277871. The next prime is 21277901. The reversal of 21277893 is 39877212.

It is not a de Polignac number, because 21277893 - 2²¹ = 19180741 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21277813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10243 + ... + 12143.

It is an arithmetic number, because the mean of its divisors is an integer number (1118376).

Almost surely, 2^21277893 is an apocalyptic number.

It is an amenable number.

21277893 is a deficient number, since it is larger than the sum of its proper divisors (14510139).

21277893 is a wasteful number, since it uses less digits than its factorization.

21277893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1965.

The product of its digits is 42336, while the sum is 39.

The square root of 21277893 is about 4612.7966571268. The cubic root of 21277893 is about 277.1040501944.

The spelling of 21277893 in words is "twenty-one million, two hundred seventy-seven thousand, eight hundred ninety-three".