1151981778 has 32 divisors (see below), whose sum is σ = 2445218496. Its totient is φ = 360557568.

The previous prime is 1151981773. The next prime is 1151981813. The reversal of 1151981778 is 8771891511.

It is not an unprimeable number, because it can be changed into a prime (1151981773) 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, 31125 + ... + 57207.

It is an arithmetic number, because the mean of its divisors is an integer number (76413078).

Almost surely, 2^1151981778 is an apocalyptic number.

1151981778 is an abundant number, since it is smaller than the sum of its proper divisors (1293236718).

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

1151981778 is a wasteful number, since it uses less digits than its factorization.

1151981778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26538.

The product of its digits is 141120, while the sum is 48.

The square root of 1151981778 is about 33940.8570604810. The cubic root of 1151981778 is about 1048.2910304380.

The spelling of 1151981778 in words is "one billion, one hundred fifty-one million, nine hundred eighty-one thousand, seven hundred seventy-eight".