21345690496 has 64 divisors (see below), whose sum is σ = 45834001920. Its totient is φ = 9843628032.

The previous prime is 21345690493. The next prime is 21345690503. The reversal of 21345690496 is 69409654312.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21345690493) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2280001 + ... + 2289343.

It is an arithmetic number, because the mean of its divisors is an integer number (716156280).

Almost surely, 2^21345690496 is an apocalyptic number.

21345690496 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21345690496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22917000960).

21345690496 is an abundant number, since it is smaller than the sum of its proper divisors (24488311424).

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

21345690496 is a wasteful number, since it uses less digits than its factorization.

21345690496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10743 (or 10731 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 49.

The spelling of 21345690496 in words is "twenty-one billion, three hundred forty-five million, six hundred ninety thousand, four hundred ninety-six".