161640587 has 2 divisors, whose sum is σ = 161640588. Its totient is φ = 161640586.

The previous prime is 161640529. The next prime is 161640593. The reversal of 161640587 is 785046161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161640587 - 2⁸ = 161640331 is a prime.

It is a super-2 number, since 2×161640587² = 52255358731409138, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161640587.

It is not a weakly prime, because it can be changed into another prime (161640187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80820293 + 80820294.

It is an arithmetic number, because the mean of its divisors is an integer number (80820294).

Almost surely, 2^161640587 is an apocalyptic number.

161640587 is a deficient number, since it is larger than the sum of its proper divisors (1).

161640587 is an equidigital number, since it uses as much as digits as its factorization.

161640587 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 38.

The square root of 161640587 is about 12713.7951454316. The cubic root of 161640587 is about 544.7327331914.

The spelling of 161640587 in words is "one hundred sixty-one million, six hundred forty thousand, five hundred eighty-seven".