21319817610 has 128 divisors (see below), whose sum is σ = 63119347200. Its totient is φ = 4487970816.

The previous prime is 21319817609. The next prime is 21319817641. The reversal of 21319817610 is 1671891312.

It is a super-2 number, since 2×21319817610² (a number of 21 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1217074 + ... + 1234466.

It is an arithmetic number, because the mean of its divisors is an integer number (493119900).

Almost surely, 2^21319817610 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21319817610, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31559673600).

21319817610 is an abundant number, since it is smaller than the sum of its proper divisors (41799529590).

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

21319817610 is a wasteful number, since it uses less digits than its factorization.

21319817610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17872.

The product of its (nonzero) digits is 18144, while the sum is 39.

The spelling of 21319817610 in words is "twenty-one billion, three hundred nineteen million, eight hundred seventeen thousand, six hundred ten".