1670857961 has 2 divisors, whose sum is σ = 1670857962. Its totient is φ = 1670857960.

The previous prime is 1670857949. The next prime is 1670857963. The reversal of 1670857961 is 1697580761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1617567961 + 53290000 = 40219^2 + 7300^2 .

It is an emirp because it is prime and its reverse (1697580761) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1670857961 - 2³⁰ = 597116137 is a prime.

Together with 1670857963, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1670857963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 835428980 + 835428981.

It is an arithmetic number, because the mean of its divisors is an integer number (835428981).

Almost surely, 2^1670857961 is an apocalyptic number.

It is an amenable number.

1670857961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1670857961 is an equidigital number, since it uses as much as digits as its factorization.

1670857961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 50.

The square root of 1670857961 is about 40876.1294767496. The cubic root of 1670857961 is about 1186.6241353253.

The spelling of 1670857961 in words is "one billion, six hundred seventy million, eight hundred fifty-seven thousand, nine hundred sixty-one".