70231561 has 4 divisors (see below), whose sum is σ = 70564624. Its totient is φ = 69898500.

The previous prime is 70231549. The next prime is 70231613. The reversal of 70231561 is 16513207.

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.

It is a cyclic number.

It is not a de Polignac number, because 70231561 - 2¹¹ = 70229513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70231501) 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, 166215 + ... + 166636.

It is an arithmetic number, because the mean of its divisors is an integer number (17641156).

Almost surely, 2^70231561 is an apocalyptic number.

It is an amenable number.

70231561 is a deficient number, since it is larger than the sum of its proper divisors (333063).

70231561 is a wasteful number, since it uses less digits than its factorization.

70231561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333062.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 70231561 is about 8380.4272564112. The cubic root of 70231561 is about 412.5824721541.

Adding to 70231561 its reverse (16513207), we get a palindrome (86744768).

It can be divided in two parts, 7023 and 1561, that multiplied together give a triangular number (10962903 = T₄₆₈₂).

The spelling of 70231561 in words is "seventy million, two hundred thirty-one thousand, five hundred sixty-one".