16501586640 has 320 divisors, whose sum is σ = 67135703040. Its totient is φ = 3248363520.

The previous prime is 16501586557. The next prime is 16501586653. The reversal of 16501586640 is 4668510561.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 16501586592 and 16501586601.

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, 327622 + ... + 374618.

It is an arithmetic number, because the mean of its divisors is an integer number (209799072).

Almost surely, 2^16501586640 is an apocalyptic number.

16501586640 is a gapful number since it is divisible by the number (10) 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 16501586640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33567851520).

16501586640 is an abundant number, since it is smaller than the sum of its proper divisors (50634116400).

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

16501586640 is a wasteful number, since it uses less digits than its factorization.

16501586640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47050 (or 47044 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 42.

The spelling of 16501586640 in words is "sixteen billion, five hundred one million, five hundred eighty-six thousand, six hundred forty".