16623647653 has 2 divisors, whose sum is σ = 16623647654. Its totient is φ = 16623647652.

The previous prime is 16623647633. The next prime is 16623647687. The reversal of 16623647653 is 35674632661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16620882084 + 2765569 = 128922^2 + 1663^2 .

It is an emirp because it is prime and its reverse (35674632661) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16623647653 is a prime.

It is a super-2 number, since 2×16623647653² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16623647597 and 16623647606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16623647633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8311823826 + 8311823827.

It is an arithmetic number, because the mean of its divisors is an integer number (8311823827).

Almost surely, 2^16623647653 is an apocalyptic number.

It is an amenable number.

16623647653 is a deficient number, since it is larger than the sum of its proper divisors (1).

16623647653 is an equidigital number, since it uses as much as digits as its factorization.

16623647653 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 49.

The spelling of 16623647653 in words is "sixteen billion, six hundred twenty-three million, six hundred forty-seven thousand, six hundred fifty-three".