16551217061720 has 32 divisors (see below), whose sum is σ = 40625714607120. Its totient is φ = 6018624385920.

The previous prime is 16551217061689. The next prime is 16551217061723. The reversal of 16551217061720 is 2716071215561.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16551217061723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18808200767 + ... + 18808201646.

Almost surely, 2^{16551217061720} is an apocalyptic number.

16551217061720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16551217061720 is an abundant number, since it is smaller than the sum of its proper divisors (24074497545400).

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

16551217061720 is a wasteful number, since it uses less digits than its factorization.

16551217061720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37616402435 (or 37616402431 counting only the distinct ones).

The product of its (nonzero) digits is 176400, while the sum is 44.

The spelling of 16551217061720 in words is "sixteen trillion, five hundred fifty-one billion, two hundred seventeen million, sixty-one thousand, seven hundred twenty".