1821906144 has 36 divisors (see below), whose sum is σ = 5181046416. Its totient is φ = 607301952.

The previous prime is 1821906139. The next prime is 1821906157. The reversal of 1821906144 is 4416091281.

1821906144 is a `hidden beast` number, since 18 + 21 + 9 + 0 + 614 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a junction number, because it is equal to n+sod(n) for n = 1821906099 and 1821906108.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3162744 + ... + 3163319.

It is an arithmetic number, because the mean of its divisors is an integer number (143917956).

Almost surely, 2^1821906144 is an apocalyptic number.

It is an amenable number.

1821906144 is an abundant number, since it is smaller than the sum of its proper divisors (3359140272).

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

1821906144 is a wasteful number, since it uses less digits than its factorization.

1821906144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6326079 (or 6326068 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 1821906144 is about 42683.7925212838. The cubic root of 1821906144 is about 1221.3552403644.

The spelling of 1821906144 in words is "one billion, eight hundred twenty-one million, nine hundred six thousand, one hundred forty-four".