1891872 has 36 divisors (see below), whose sum is σ = 5380830. Its totient is φ = 630528.

The previous prime is 1891861. The next prime is 1891889. The reversal of 1891872 is 2781981.

It can be written as a sum of positive squares in only one way, i.e., 1245456 + 646416 = 1116^2 + 804^2 .

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 an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2997 + ... + 3572.

2^1891872 is an apocalyptic number.

1891872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1891872 is an abundant number, since it is smaller than the sum of its proper divisors (3488958).

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

1891872 is a wasteful number, since it uses less digits than its factorization.

1891872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6585 (or 6574 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 1891872 is about 1375.4533797988. The cubic root of 1891872 is about 123.6793658741.

The spelling of 1891872 in words is "one million, eight hundred ninety-one thousand, eight hundred seventy-two".