161315511 has 8 divisors (see below), whose sum is σ = 245814144. Its totient is φ = 92180280.

The previous prime is 161315509. The next prime is 161315513. The reversal of 161315511 is 115513161.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (161315509) and next prime (161315513).

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

It is not a de Polignac number, because 161315511 - 2¹ = 161315509 is a prime.

It is a super-3 number, since 3×161315511³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161315513) 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, 3840825 + ... + 3840866.

It is an arithmetic number, because the mean of its divisors is an integer number (30726768).

Almost surely, 2^161315511 is an apocalyptic number.

161315511 is a deficient number, since it is larger than the sum of its proper divisors (84498633).

161315511 is an equidigital number, since it uses as much as digits as its factorization.

161315511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7681701.

The product of its digits is 450, while the sum is 24.

The square root of 161315511 is about 12701.0043303669. The cubic root of 161315511 is about 544.3673167604.

Adding to 161315511 its reverse (115513161), we get a palindrome (276828672).

The spelling of 161315511 in words is "one hundred sixty-one million, three hundred fifteen thousand, five hundred eleven".