1861269440 has 28 divisors (see below), whose sum is σ = 4432148616. Its totient is φ = 744507648.

The previous prime is 1861269437. The next prime is 1861269461. The reversal of 1861269440 is 449621681.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 2907914 + ... + 2908553.

It is an arithmetic number, because the mean of its divisors is an integer number (158291022).

Almost surely, 2^1861269440 is an apocalyptic number.

1861269440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1861269440 is an abundant number, since it is smaller than the sum of its proper divisors (2570879176).

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

1861269440 is an equidigital number, since it uses as much as digits as its factorization.

1861269440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5816484 (or 5816474 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 1861269440 is about 43142.4320130426. The cubic root of 1861269440 is about 1230.0886621703.

The spelling of 1861269440 in words is "one billion, eight hundred sixty-one million, two hundred sixty-nine thousand, four hundred forty".