16991420544 has 320 divisors, whose sum is σ = 58376672640. Its totient is φ = 4805443584.

The previous prime is 16991420527. The next prime is 16991420597. The reversal of 16991420544 is 44502419961.

16991420544 is a `hidden beast` number, since 1 + 6 + 99 + 14 + 2 + 0 + 544 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 16991420544.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 7474192 + ... + 7476464.

It is an arithmetic number, because the mean of its divisors is an integer number (182427102).

Almost surely, 2^16991420544 is an apocalyptic number.

16991420544 is a gapful number since it is divisible by the number (14) 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 16991420544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29188336320).

16991420544 is an abundant number, since it is smaller than the sum of its proper divisors (41385252096).

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

16991420544 is a wasteful number, since it uses less digits than its factorization.

16991420544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2409 (or 2388 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 16991420544 in words is "sixteen billion, nine hundred ninety-one million, four hundred twenty thousand, five hundred forty-four".