16520537280 has 224 divisors, whose sum is σ = 57416200128. Its totient is φ = 3999744000.

The previous prime is 16520537279. The next prime is 16520537281. The reversal of 16520537280 is 8273502561.

It is an interprime number because it is at equal distance from previous prime (16520537279) and next prime (16520537281).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (16520537281) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 750430 + ... + 772130.

It is an arithmetic number, because the mean of its divisors is an integer number (256322322).

Almost surely, 2^16520537280 is an apocalyptic number.

16520537280 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 16520537280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28708100064).

16520537280 is an abundant number, since it is smaller than the sum of its proper divisors (40895662848).

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

16520537280 is a wasteful number, since it uses less digits than its factorization.

16520537280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21795 (or 21785 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 39.

The spelling of 16520537280 in words is "sixteen billion, five hundred twenty million, five hundred thirty-seven thousand, two hundred eighty".