1813287420 has 144 divisors (see below), whose sum is σ = 6616995840. Its totient is φ = 392646528.

The previous prime is 1813287419. The next prime is 1813287449. The reversal of 1813287420 is 247823181.

It is a super-2 number, since 2×1813287420² = 6576022535060512800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13932 + ... + 61811.

It is an arithmetic number, because the mean of its divisors is an integer number (45951360).

Almost surely, 2^1813287420 is an apocalyptic number.

1813287420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1813287420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3308497920).

1813287420 is an abundant number, since it is smaller than the sum of its proper divisors (4803708420).

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

1813287420 is a wasteful number, since it uses less digits than its factorization.

1813287420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75784 (or 75779 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 1813287420 is about 42582.7126895410. The cubic root of 1813287420 is about 1219.4262777644.

The spelling of 1813287420 in words is "one billion, eight hundred thirteen million, two hundred eighty-seven thousand, four hundred twenty".