1861421420 has 12 divisors (see below), whose sum is σ = 3908985024. Its totient is φ = 744568560.

The previous prime is 1861421411. The next prime is 1861421423. The reversal of 1861421420 is 241241681.

It is not an unprimeable number, because it can be changed into a prime (1861421423) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 46535516 + ... + 46535555.

It is an arithmetic number, because the mean of its divisors is an integer number (325748752).

Almost surely, 2^1861421420 is an apocalyptic number.

1861421420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1861421420 is an abundant number, since it is smaller than the sum of its proper divisors (2047563604).

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

1861421420 is a wasteful number, since it uses less digits than its factorization.

1861421420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93071080 (or 93071078 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 1861421420 is about 43144.1933520607. The cubic root of 1861421420 is about 1230.1221417914.

The spelling of 1861421420 in words is "one billion, eight hundred sixty-one million, four hundred twenty-one thousand, four hundred twenty".