161431253513511 has 24 divisors (see below), whose sum is σ = 232231065442560. Its totient is φ = 99469835225280.

The previous prime is 161431253513507. The next prime is 161431253513557. The reversal of 161431253513511 is 115315352134161.

It is not a de Polignac number, because 161431253513511 - 2² = 161431253513507 is a prime.

It is a super-2 number, since 2×161431253513511² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161431253513111) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 842297775 + ... + 842489408.

It is an arithmetic number, because the mean of its divisors is an integer number (9676294393440).

Almost surely, 2^{161431253513511} is an apocalyptic number.

161431253513511 is a deficient number, since it is larger than the sum of its proper divisors (70799811929049).

161431253513511 is a wasteful number, since it uses less digits than its factorization.

161431253513511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1684787287 (or 1684787246 counting only the distinct ones).

The product of its digits is 162000, while the sum is 42.

The spelling of 161431253513511 in words is "one hundred sixty-one trillion, four hundred thirty-one billion, two hundred fifty-three million, five hundred thirteen thousand, five hundred eleven".