16651001565 has 48 divisors (see below), whose sum is σ = 31519665216. Its totient is φ = 8064460800.

The previous prime is 16651001561. The next prime is 16651001569. The reversal of 16651001565 is 56510015661.

It is an interprime number because it is at equal distance from previous prime (16651001561) and next prime (16651001569).

It is not a de Polignac number, because 16651001565 - 2² = 16651001561 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16651001561) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 451005 + ... + 486525.

It is an arithmetic number, because the mean of its divisors is an integer number (656659692).

Almost surely, 2^16651001565 is an apocalyptic number.

16651001565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16651001565 is a deficient number, since it is larger than the sum of its proper divisors (14868663651).

16651001565 is a wasteful number, since it uses less digits than its factorization.

16651001565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36490 (or 36487 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

It can be divided in two parts, 1 and 6651001565, that added together give a palindrome (6651001566).

The spelling of 16651001565 in words is "sixteen billion, six hundred fifty-one million, one thousand, five hundred sixty-five".