16661505157 has 4 divisors (see below), whose sum is σ = 18176187456. Its totient is φ = 15146822860.

The previous prime is 16661505143. The next prime is 16661505167. The reversal of 16661505157 is 75150516661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16661505157 - 2¹¹ = 16661503109 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 (16661505167) 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, 757341133 + ... + 757341154.

It is an arithmetic number, because the mean of its divisors is an integer number (4544046864).

Almost surely, 2^16661505157 is an apocalyptic number.

It is an amenable number.

16661505157 is a deficient number, since it is larger than the sum of its proper divisors (1514682299).

16661505157 is a wasteful number, since it uses less digits than its factorization.

16661505157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1514682298.

The product of its (nonzero) digits is 189000, while the sum is 43.

The spelling of 16661505157 in words is "sixteen billion, six hundred sixty-one million, five hundred five thousand, one hundred fifty-seven".