1691968117 has 4 divisors (see below), whose sum is σ = 1933677856. Its totient is φ = 1450258380.

The previous prime is 1691968099. The next prime is 1691968121. The reversal of 1691968117 is 7118691961.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1691968117 is a prime.

It is a super-2 number, since 2×1691968117² = 5725512217889051378, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1691960117) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120854859 + ... + 120854872.

It is an arithmetic number, because the mean of its divisors is an integer number (483419464).

Almost surely, 2^1691968117 is an apocalyptic number.

It is an amenable number.

1691968117 is a deficient number, since it is larger than the sum of its proper divisors (241709739).

1691968117 is an equidigital number, since it uses as much as digits as its factorization.

1691968117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241709738.

The product of its digits is 163296, while the sum is 49.

The square root of 1691968117 is about 41133.5400494536. The cubic root of 1691968117 is about 1191.6006323644.

The spelling of 1691968117 in words is "one billion, six hundred ninety-one million, nine hundred sixty-eight thousand, one hundred seventeen".