161739671540 has 24 divisors (see below), whose sum is σ = 339863950440. Its totient is φ = 64655746688.

The previous prime is 161739671539. The next prime is 161739671563. The reversal of 161739671540 is 45176937161.

It can be written as a sum of positive squares in 4 ways, for example, as 1159947364 + 160579724176 = 34058^2 + 400724^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2474555 + ... + 2539074.

It is an arithmetic number, because the mean of its divisors is an integer number (14160997935).

Almost surely, 2^161739671540 is an apocalyptic number.

161739671540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161739671540 is an abundant number, since it is smaller than the sum of its proper divisors (178124278900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161739671540 is a wasteful number, since it uses less digits than its factorization.

161739671540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5015251 (or 5015249 counting only the distinct ones).

The product of its (nonzero) digits is 952560, while the sum is 50.

The spelling of 161739671540 in words is "one hundred sixty-one billion, seven hundred thirty-nine million, six hundred seventy-one thousand, five hundred forty".