16721253505 has 8 divisors (see below), whose sum is σ = 21889641024. Its totient is φ = 12160911600.

The previous prime is 16721253503. The next prime is 16721253511. The reversal of 16721253505 is 50535212761.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16721253505 - 2¹ = 16721253503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16721253503) 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, 152011341 + ... + 152011450.

It is an arithmetic number, because the mean of its divisors is an integer number (2736205128).

Almost surely, 2^16721253505 is an apocalyptic number.

It is an amenable number.

16721253505 is a deficient number, since it is larger than the sum of its proper divisors (5168387519).

16721253505 is a wasteful number, since it uses less digits than its factorization.

16721253505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304022807.

The product of its (nonzero) digits is 63000, while the sum is 37.

The spelling of 16721253505 in words is "sixteen billion, seven hundred twenty-one million, two hundred fifty-three thousand, five hundred five".