161581687060 has 12 divisors (see below), whose sum is σ = 339321542868. Its totient is φ = 64632674816.

The previous prime is 161581687027. The next prime is 161581687063. The reversal of 161581687060 is 60786185161.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 50954935824 + 110626751236 = 225732^2 + 332606^2 .

It is a super-2 number, since 2×161581687060² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161581686995 and 161581687013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161581687063) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4039542157 + ... + 4039542196.

It is an arithmetic number, because the mean of its divisors is an integer number (28276795239).

Almost surely, 2^161581687060 is an apocalyptic number.

161581687060 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161581687060 is an abundant number, since it is smaller than the sum of its proper divisors (177739855808).

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

161581687060 is a wasteful number, since it uses less digits than its factorization.

161581687060 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8079084362 (or 8079084360 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 49.

The spelling of 161581687060 in words is "one hundred sixty-one billion, five hundred eighty-one million, six hundred eighty-seven thousand, sixty".