70161561 has 24 divisors (see below), whose sum is σ = 104569920. Its totient is φ = 45309600.

The previous prime is 70161517. The next prime is 70161563. The reversal of 70161561 is 16516107.

It is not a de Polignac number, because 70161561 - 2¹¹ = 70159513 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (70161563) 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, 36771 + ... + 38631.

It is an arithmetic number, because the mean of its divisors is an integer number (4357080).

Almost surely, 2^70161561 is an apocalyptic number.

70161561 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

70161561 is a deficient number, since it is larger than the sum of its proper divisors (34408359).

70161561 is a wasteful number, since it uses less digits than its factorization.

70161561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1997 (or 1994 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 70161561 is about 8376.2498171915. The cubic root of 70161561 is about 412.4453525403.

Adding to 70161561 its reverse (16516107), we get a palindrome (86677668).

The spelling of 70161561 in words is "seventy million, one hundred sixty-one thousand, five hundred sixty-one".