70161521 has 4 divisors (see below), whose sum is σ = 70273344. Its totient is φ = 70049700.

The previous prime is 70161517. The next prime is 70161563. The reversal of 70161521 is 12516107.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12516107 = 2267 ⋅5521.

It is a cyclic number.

It is not a de Polignac number, because 70161521 - 2² = 70161517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70161571) 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, 54965 + ... + 56226.

It is an arithmetic number, because the mean of its divisors is an integer number (17568336).

Almost surely, 2^70161521 is an apocalyptic number.

It is an amenable number.

70161521 is a deficient number, since it is larger than the sum of its proper divisors (111823).

70161521 is a wasteful number, since it uses less digits than its factorization.

70161521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111822.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 70161521 is about 8376.2474294877. The cubic root of 70161521 is about 412.4452741602.

Adding to 70161521 its reverse (12516107), we get a palindrome (82677628).

The spelling of 70161521 in words is "seventy million, one hundred sixty-one thousand, five hundred twenty-one".