21347331516 has 192 divisors, whose sum is σ = 66883891200. Its totient is φ = 5751891648.

The previous prime is 21347331503. The next prime is 21347331539. The reversal of 21347331516 is 61513374312.

21347331516 is a `hidden beast` number, since 2 + 134 + 7 + 3 + 3 + 1 + 516 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3257355 + ... + 3263901.

It is an arithmetic number, because the mean of its divisors is an integer number (348353600).

Almost surely, 2^21347331516 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21347331516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33441945600).

21347331516 is an abundant number, since it is smaller than the sum of its proper divisors (45536559684).

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

21347331516 is a wasteful number, since it uses less digits than its factorization.

21347331516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6813 (or 6805 counting only the distinct ones).

The product of its digits is 45360, while the sum is 36.

The spelling of 21347331516 in words is "twenty-one billion, three hundred forty-seven million, three hundred thirty-one thousand, five hundred sixteen".