1694080981 has 4 divisors (see below), whose sum is σ = 1694375500. Its totient is φ = 1693786464.

The previous prime is 1694080967. The next prime is 1694081003. The reversal of 1694080981 is 1890804961.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1890804961 = 10601 ⋅178361.

It can be written as a sum of positive squares in 2 ways, for example, as 876692881 + 817388100 = 29609^2 + 28590^2 .

It is a cyclic number.

It is not a de Polignac number, because 1694080981 - 2⁹ = 1694080469 is a prime.

It is a super-2 number, since 2×1694080981² = 5739820740371844722, 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 (1694080931) 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, 138456 + ... + 150193.

It is an arithmetic number, because the mean of its divisors is an integer number (423593875).

Almost surely, 2^1694080981 is an apocalyptic number.

It is an amenable number.

1694080981 is a deficient number, since it is larger than the sum of its proper divisors (294519).

1694080981 is an equidigital number, since it uses as much as digits as its factorization.

1694080981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294518.

The product of its (nonzero) digits is 124416, while the sum is 46.

The square root of 1694080981 is about 41159.2150192396. The cubic root of 1694080981 is about 1192.0964342222.

The spelling of 1694080981 in words is "one billion, six hundred ninety-four million, eighty thousand, nine hundred eighty-one".