16720673437 has 4 divisors (see below), whose sum is σ = 18006879100. Its totient is φ = 15434467776.

The previous prime is 16720673419. The next prime is 16720673449. The reversal of 16720673437 is 73437602761.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73437602761 = 43 ⋅1707851227.

It can be written as a sum of positive squares in 2 ways, for example, as 10271619801 + 6449053636 = 101349^2 + 80306^2 .

It is a de Polignac number, because none of the positive numbers 2^k-16720673437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16720673477) 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, 643102812 + ... + 643102837.

It is an arithmetic number, because the mean of its divisors is an integer number (4501719775).

Almost surely, 2^16720673437 is an apocalyptic number.

It is an amenable number.

16720673437 is a deficient number, since it is larger than the sum of its proper divisors (1286205663).

16720673437 is a wasteful number, since it uses less digits than its factorization.

16720673437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1286205662.

The product of its (nonzero) digits is 889056, while the sum is 46.

The spelling of 16720673437 in words is "sixteen billion, seven hundred twenty million, six hundred seventy-three thousand, four hundred thirty-seven".