21278770683 has 4 divisors (see below), whose sum is σ = 28371694248. Its totient is φ = 14185847120.

The previous prime is 21278770663. The next prime is 21278770691. The reversal of 21278770683 is 38607787212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21278770683 - 2³⁰ = 20205028859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21278770663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3546461778 + ... + 3546461783.

It is an arithmetic number, because the mean of its divisors is an integer number (7092923562).

Almost surely, 2^21278770683 is an apocalyptic number.

21278770683 is a deficient number, since it is larger than the sum of its proper divisors (7092923565).

21278770683 is an equidigital number, since it uses as much as digits as its factorization.

21278770683 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7092923564.

The product of its (nonzero) digits is 1580544, while the sum is 51.

The spelling of 21278770683 in words is "twenty-one billion, two hundred seventy-eight million, seven hundred seventy thousand, six hundred eighty-three".