16517555640 has 192 divisors, whose sum is σ = 58945592160. Its totient is φ = 4145541120.

The previous prime is 16517555617. The next prime is 16517555647. The reversal of 16517555640 is 4655571561.

It is a happy number.

16517555640 is a `hidden beast` number, since 1 + 6 + 51 + 7 + 5 + 556 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16517555647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 115260 + ... + 215220.

Almost surely, 2^16517555640 is an apocalyptic number.

16517555640 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 16517555640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29472796080).

16517555640 is an abundant number, since it is smaller than the sum of its proper divisors (42428036520).

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

16517555640 is a wasteful number, since it uses less digits than its factorization.

16517555640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100004 (or 99988 counting only the distinct ones).

The product of its (nonzero) digits is 630000, while the sum is 45.

The spelling of 16517555640 in words is "sixteen billion, five hundred seventeen million, five hundred fifty-five thousand, six hundred forty".