1618817772 has 48 divisors (see below), whose sum is σ = 4437603072. Its totient is φ = 452815680.

The previous prime is 1618817647. The next prime is 1618817791. The reversal of 1618817772 is 2777188161.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 469968 + ... + 473399.

It is an arithmetic number, because the mean of its divisors is an integer number (92450064).

Almost surely, 2^1618817772 is an apocalyptic number.

1618817772 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1618817772 is an abundant number, since it is smaller than the sum of its proper divisors (2818785300).

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

1618817772 is a wasteful number, since it uses less digits than its factorization.

1618817772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 943398 (or 943396 counting only the distinct ones).

The product of its digits is 263424, while the sum is 48.

The square root of 1618817772 is about 40234.5345691981. The cubic root of 1618817772 is about 1174.1745273843.

It can be divided in two parts, 161881 and 7772, that added together give a triangular number (169653 = T₅₈₂).

The spelling of 1618817772 in words is "one billion, six hundred eighteen million, eight hundred seventeen thousand, seven hundred seventy-two".