165555136251 has 12 divisors (see below), whose sum is σ = 247992056312. Its totient is φ = 110370090672.

The previous prime is 165555136231. The next prime is 165555136297. The reversal of 165555136251 is 152631555561.

165555136251 is a `hidden beast` number, since 1 + 6 + 5 + 5 + 5 + 5 + 13 + 625 + 1 = 666.

It is not a de Polignac number, because 165555136251 - 2¹³ = 165555128059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165555136197 and 165555136206.

It is not an unprimeable number, because it can be changed into a prime (165555136231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 340648186 + ... + 340648671.

Almost surely, 2^165555136251 is an apocalyptic number.

165555136251 is a deficient number, since it is larger than the sum of its proper divisors (82436920061).

165555136251 is an frugal number, since it uses more digits than its factorization.

165555136251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681296872 (or 681296860 counting only the distinct ones).

The product of its digits is 675000, while the sum is 45.

The spelling of 165555136251 in words is "one hundred sixty-five billion, five hundred fifty-five million, one hundred thirty-six thousand, two hundred fifty-one".