1667610961 has 2 divisors, whose sum is σ = 1667610962. Its totient is φ = 1667610960.

The previous prime is 1667610949. The next prime is 1667611007. The reversal of 1667610961 is 1690167661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1658118400 + 9492561 = 40720^2 + 3081^2 .

It is a cyclic number.

It is not a de Polignac number, because 1667610961 - 2¹⁵ = 1667578193 is a prime.

It is not a weakly prime, because it can be changed into another prime (1667610911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833805480 + 833805481.

It is an arithmetic number, because the mean of its divisors is an integer number (833805481).

Almost surely, 2^1667610961 is an apocalyptic number.

It is an amenable number.

1667610961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1667610961 is an equidigital number, since it uses as much as digits as its factorization.

1667610961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81648, while the sum is 43.

The square root of 1667610961 is about 40836.3926051261. The cubic root of 1667610961 is about 1185.8549761674.

The spelling of 1667610961 in words is "one billion, six hundred sixty-seven million, six hundred ten thousand, nine hundred sixty-one".