16399451801 has 4 divisors (see below), whose sum is σ = 16399713204. Its totient is φ = 16399190400.

The previous prime is 16399451777. The next prime is 16399451813. The reversal of 16399451801 is 10815499361.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 12204946576 + 4194505225 = 110476^2 + 64765^2 .

It is a cyclic number.

It is not a de Polignac number, because 16399451801 - 2⁶ = 16399451737 is a prime.

It is a deceptive number, since it divides R_16399451800.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16399451851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26141 + ... + 182981.

It is an arithmetic number, because the mean of its divisors is an integer number (4099928301).

Almost surely, 2^16399451801 is an apocalyptic number.

16399451801 is the 104561-st pentagonal number.

It is an amenable number.

16399451801 is a deficient number, since it is larger than the sum of its proper divisors (261403).

16399451801 is a wasteful number, since it uses less digits than its factorization.

16399451801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261402.

The product of its (nonzero) digits is 233280, while the sum is 47.

The spelling of 16399451801 in words is "sixteen billion, three hundred ninety-nine million, four hundred fifty-one thousand, eight hundred one".