83997644640 has 1536 divisors, whose sum is σ = 368709304320. Its totient is φ = 15571353600.

The previous prime is 83997644629. The next prime is 83997644723. The reversal of 83997644640 is 4644679938.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 943793716 + ... + 943793804.

It is an arithmetic number, because the mean of its divisors is an integer number (240045120).

Almost surely, 2^83997644640 is an apocalyptic number.

83997644640 is a gapful number since it is divisible by the number (80) 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 83997644640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184354652160).

83997644640 is an abundant number, since it is smaller than the sum of its proper divisors (284711659680).

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

83997644640 is a wasteful number, since it uses less digits than its factorization.

83997644640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 31352832, while the sum is 60.

The spelling of 83997644640 in words is "eighty-three billion, nine hundred ninety-seven million, six hundred forty-four thousand, six hundred forty".