167961509 has 2 divisors, whose sum is σ = 167961510. Its totient is φ = 167961508.

The previous prime is 167961491. The next prime is 167961511. The reversal of 167961509 is 905169761.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127193284 + 40768225 = 11278^2 + 6385^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-167961509 is a prime.

It is a super-2 number, since 2×167961509² = 56422137011114162, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 167961511, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 167961509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (167961559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83980754 + 83980755.

It is an arithmetic number, because the mean of its divisors is an integer number (83980755).

Almost surely, 2^167961509 is an apocalyptic number.

It is an amenable number.

167961509 is a deficient number, since it is larger than the sum of its proper divisors (1).

167961509 is an equidigital number, since it uses as much as digits as its factorization.

167961509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 102060, while the sum is 44.

The square root of 167961509 is about 12959.9964891971. The cubic root of 167961509 is about 551.7426916803.

The spelling of 167961509 in words is "one hundred sixty-seven million, nine hundred sixty-one thousand, five hundred nine".