161537077813 has 2 divisors, whose sum is σ = 161537077814. Its totient is φ = 161537077812.

The previous prime is 161537077811. The next prime is 161537077903. The reversal of 161537077813 is 318770735161.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149519875684 + 12017202129 = 386678^2 + 109623^2 .

It is a cyclic number.

It is not a de Polignac number, because 161537077813 - 2¹ = 161537077811 is a prime.

It is a super-3 number, since 3×161537077813³ (a number of 35 digits) contains 333 as substring.

Together with 161537077811, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161537077811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80768538906 + 80768538907.

It is an arithmetic number, because the mean of its divisors is an integer number (80768538907).

Almost surely, 2^161537077813 is an apocalyptic number.

It is an amenable number.

161537077813 is a deficient number, since it is larger than the sum of its proper divisors (1).

161537077813 is an equidigital number, since it uses as much as digits as its factorization.

161537077813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 740880, while the sum is 49.

The spelling of 161537077813 in words is "one hundred sixty-one billion, five hundred thirty-seven million, seventy-seven thousand, eight hundred thirteen".