16625146781 has 4 divisors (see below), whose sum is σ = 16633246812. Its totient is φ = 16617046752.

The previous prime is 16625146771. The next prime is 16625146799. The reversal of 16625146781 is 18764152661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7151239225 + 9473907556 = 84565^2 + 97334^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16625146781 is a prime.

It is a super-4 number, since 4×16625146781⁴ (a number of 42 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16625146751) 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, 4046936 + ... + 4051041.

It is an arithmetic number, because the mean of its divisors is an integer number (4158311703).

Almost surely, 2^16625146781 is an apocalyptic number.

It is an amenable number.

16625146781 is a deficient number, since it is larger than the sum of its proper divisors (8100031).

16625146781 is an equidigital number, since it uses as much as digits as its factorization.

16625146781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8100030.

The product of its digits is 483840, while the sum is 47.

The spelling of 16625146781 in words is "sixteen billion, six hundred twenty-five million, one hundred forty-six thousand, seven hundred eighty-one".