1581195798 has 144 divisors (see below), whose sum is σ = 4317243840. Its totient is φ = 414554112.

The previous prime is 1581195793. The next prime is 1581195821. The reversal of 1581195798 is 8975911851.

It is a happy number.

1581195798 is a `hidden beast` number, since 1 + 58 + 1 + 19 + 579 + 8 = 666.

1581195798 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×1581195798² = 5000360303225713608, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581195793) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2740086 + ... + 2740662.

It is an arithmetic number, because the mean of its divisors is an integer number (29980860).

Almost surely, 2^1581195798 is an apocalyptic number.

1581195798 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1581195798, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2158621920).

1581195798 is an abundant number, since it is smaller than the sum of its proper divisors (2736048042).

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

1581195798 is a wasteful number, since it uses less digits than its factorization.

1581195798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 851 (or 841 counting only the distinct ones).

The product of its digits is 907200, while the sum is 54.

The square root of 1581195798 is about 39764.2527655179. The cubic root of 1581195798 is about 1165.0070420224.

The spelling of 1581195798 in words is "one billion, five hundred eighty-one million, one hundred ninety-five thousand, seven hundred ninety-eight".