21467644660 has 48 divisors (see below), whose sum is σ = 56206200960. Its totient is φ = 6691213440.

The previous prime is 21467644657. The next prime is 21467644663. The reversal of 21467644660 is 6644676412.

It is an interprime number because it is at equal distance from previous prime (21467644657) and next prime (21467644663).

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21467644660.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21467644663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6968475 + ... + 6971554.

It is an arithmetic number, because the mean of its divisors is an integer number (1170962520).

Almost surely, 2^21467644660 is an apocalyptic number.

21467644660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21467644660 is an abundant number, since it is smaller than the sum of its proper divisors (34738556300).

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

21467644660 is a wasteful number, since it uses less digits than its factorization.

21467644660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13940056 (or 13940054 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 46.

The spelling of 21467644660 in words is "twenty-one billion, four hundred sixty-seven million, six hundred forty-four thousand, six hundred sixty".