161451171521 has 8 divisors (see below), whose sum is σ = 163036577088. Its totient is φ = 159871114000.

The previous prime is 161451171487. The next prime is 161451171547. The reversal of 161451171521 is 125171154161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161451171521 is a prime.

It is a super-2 number, since 2×161451171521² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161451179521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1276325 + ... + 1397106.

It is an arithmetic number, because the mean of its divisors is an integer number (20379572136).

Almost surely, 2^161451171521 is an apocalyptic number.

It is an amenable number.

161451171521 is a deficient number, since it is larger than the sum of its proper divisors (1585405567).

161451171521 is a wasteful number, since it uses less digits than its factorization.

161451171521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2674023.

The product of its digits is 8400, while the sum is 35.

The spelling of 161451171521 in words is "one hundred sixty-one billion, four hundred fifty-one million, one hundred seventy-one thousand, five hundred twenty-one".