1836721640 has 64 divisors (see below), whose sum is σ = 4684780800. Its totient is φ = 642477312.

The previous prime is 1836721631. The next prime is 1836721669. The reversal of 1836721640 is 461276381.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 1836721594 and 1836721603.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83072 + ... + 102831.

It is an arithmetic number, because the mean of its divisors is an integer number (73199700).

Almost surely, 2^1836721640 is an apocalyptic number.

1836721640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1836721640 is an abundant number, since it is smaller than the sum of its proper divisors (2848059160).

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

1836721640 is a wasteful number, since it uses less digits than its factorization.

1836721640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185946 (or 185942 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 1836721640 is about 42856.9905616342. The cubic root of 1836721640 is about 1224.6569390591.

The spelling of 1836721640 in words is "one billion, eight hundred thirty-six million, seven hundred twenty-one thousand, six hundred forty".