161672857 has 2 divisors, whose sum is σ = 161672858. Its totient is φ = 161672856.

The previous prime is 161672851. The next prime is 161672891. The reversal of 161672857 is 758276161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 153239641 + 8433216 = 12379^2 + 2904^2 .

It is a cyclic number.

It is not a de Polignac number, because 161672857 - 2¹⁹ = 161148569 is a prime.

It is a super-2 number, since 2×161672857² = 52276225381084898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161672851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80836428 + 80836429.

It is an arithmetic number, because the mean of its divisors is an integer number (80836429).

Almost surely, 2^161672857 is an apocalyptic number.

It is an amenable number.

161672857 is a deficient number, since it is larger than the sum of its proper divisors (1).

161672857 is an equidigital number, since it uses as much as digits as its factorization.

161672857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 141120, while the sum is 43.

The square root of 161672857 is about 12715.0641760079. The cubic root of 161672857 is about 544.7689810092.

The spelling of 161672857 in words is "one hundred sixty-one million, six hundred seventy-two thousand, eight hundred fifty-seven".