1820091540 has 24 divisors (see below), whose sum is σ = 5096256480. Its totient is φ = 485357728.

The previous prime is 1820091521. The next prime is 1820091541. The reversal of 1820091540 is 451900281.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1820091498 and 1820091507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1820091541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15167370 + ... + 15167489.

It is an arithmetic number, because the mean of its divisors is an integer number (212344020).

Almost surely, 2^1820091540 is an apocalyptic number.

1820091540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1820091540 is an abundant number, since it is smaller than the sum of its proper divisors (3276164940).

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

1820091540 is a wasteful number, since it uses less digits than its factorization.

1820091540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30334871 (or 30334869 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 30.

The square root of 1820091540 is about 42662.5308672610. The cubic root of 1820091540 is about 1220.9496189740.

The spelling of 1820091540 in words is "one billion, eight hundred twenty million, ninety-one thousand, five hundred forty".