1581363378 has 48 divisors (see below), whose sum is σ = 4087884960. Its totient is φ = 451817352.

The previous prime is 1581363349. The next prime is 1581363397. The reversal of 1581363378 is 8733631851.

1581363378 is a `hidden beast` number, since 1 + 5 + 8 + 1 + 3 + 633 + 7 + 8 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 296176 + ... + 301467.

It is an arithmetic number, because the mean of its divisors is an integer number (85164270).

Almost surely, 2^1581363378 is an apocalyptic number.

1581363378 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1581363378 is an abundant number, since it is smaller than the sum of its proper divisors (2506521582).

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

1581363378 is a wasteful number, since it uses less digits than its factorization.

1581363378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 597668 (or 597655 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 1581363378 is about 39766.3598786713. The cubic root of 1581363378 is about 1165.0481975799.

The spelling of 1581363378 in words is "one billion, five hundred eighty-one million, three hundred sixty-three thousand, three hundred seventy-eight".