1161771856 has 20 divisors (see below), whose sum is σ = 2572495072. Its totient is φ = 497902176.

The previous prime is 1161771827. The next prime is 1161771907. The reversal of 1161771856 is 6581771611.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5186370 + ... + 5186593.

Almost surely, 2^1161771856 is an apocalyptic number.

1161771856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1161771856 is an abundant number, since it is smaller than the sum of its proper divisors (1410723216).

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

1161771856 is a wasteful number, since it uses less digits than its factorization.

1161771856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10372978 (or 10372972 counting only the distinct ones).

The product of its digits is 70560, while the sum is 43.

The square root of 1161771856 is about 34084.7745481762. The cubic root of 1161771856 is about 1051.2522794238.

The spelling of 1161771856 in words is "one billion, one hundred sixty-one million, seven hundred seventy-one thousand, eight hundred fifty-six".