165680540949 has 144 divisors (see below), whose sum is σ = 301920299520. Its totient is φ = 78885576000.

The previous prime is 165680540947. The next prime is 165680540951. The reversal of 165680540949 is 949045086561.

It is an interprime number because it is at equal distance from previous prime (165680540947) and next prime (165680540951).

It is not a de Polignac number, because 165680540949 - 2¹ = 165680540947 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165680540947) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 46394334 + ... + 46397904.

Almost surely, 2^165680540949 is an apocalyptic number.

165680540949 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

165680540949 is a deficient number, since it is larger than the sum of its proper divisors (136239758571).

165680540949 is a wasteful number, since it uses less digits than its factorization.

165680540949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3684 (or 3642 counting only the distinct ones).

The product of its (nonzero) digits is 9331200, while the sum is 57.

The spelling of 165680540949 in words is "one hundred sixty-five billion, six hundred eighty million, five hundred forty thousand, nine hundred forty-nine".