165511161050551 has 16 divisors (see below), whose sum is σ = 166734900396000. Its totient is φ = 164290552852608.

The previous prime is 165511161050453. The next prime is 165511161050567. The reversal of 165511161050551 is 155050161115561.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 165511161050551 - 2¹¹ = 165511161048503 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165511161050498 and 165511161050507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165511161057551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 968388100 + ... + 968558998.

It is an arithmetic number, because the mean of its divisors is an integer number (10420931274750).

Almost surely, 2^{165511161050551} is an apocalyptic number.

165511161050551 is a deficient number, since it is larger than the sum of its proper divisors (1223739345449).

165511161050551 is a wasteful number, since it uses less digits than its factorization.

165511161050551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180018.

The product of its (nonzero) digits is 112500, while the sum is 43.

The spelling of 165511161050551 in words is "one hundred sixty-five trillion, five hundred eleven billion, one hundred sixty-one million, fifty thousand, five hundred fifty-one".