21222670646 has 4 divisors (see below), whose sum is σ = 31834005972. Its totient is φ = 10611335322.

The previous prime is 21222670631. The next prime is 21222670687. The reversal of 21222670646 is 64607622212.

It is a happy number.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5305667660 + ... + 5305667663.

It is an arithmetic number, because the mean of its divisors is an integer number (7958501493).

Almost surely, 2^21222670646 is an apocalyptic number.

21222670646 is a deficient number, since it is larger than the sum of its proper divisors (10611335326).

21222670646 is a wasteful number, since it uses less digits than its factorization.

21222670646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10611335325.

The product of its (nonzero) digits is 96768, while the sum is 38.

The spelling of 21222670646 in words is "twenty-one billion, two hundred twenty-two million, six hundred seventy thousand, six hundred forty-six".