1681160778 has 32 divisors (see below), whose sum is σ = 4075542720. Its totient is φ = 509442480.

The previous prime is 1681160773. The next prime is 1681160797. The reversal of 1681160778 is 8770611861.

It is a happy number.

It is a super-2 number, since 2×1681160778² = 5652603122971130568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1681160773) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1414525 + ... + 1415712.

It is an arithmetic number, because the mean of its divisors is an integer number (127360710).

Almost surely, 2^1681160778 is an apocalyptic number.

1681160778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1681160778 is an abundant number, since it is smaller than the sum of its proper divisors (2394381942).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1681160778 is a wasteful number, since it uses less digits than its factorization.

1681160778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2830259 (or 2830253 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 45.

The square root of 1681160778 is about 41001.9606604367. The cubic root of 1681160778 is about 1189.0581201314.

The spelling of 1681160778 in words is "one billion, six hundred eighty-one million, one hundred sixty thousand, seven hundred seventy-eight".