1891280 has 40 divisors (see below), whose sum is σ = 4499712. Its totient is φ = 738944.

The previous prime is 1891277. The next prime is 1891283. The reversal of 1891280 is 821981.

It is an interprime number because it is at equal distance from previous prime (1891277) and next prime (1891283).

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1891283) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3509 + ... + 4011.

2^1891280 is an apocalyptic number.

1891280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1891280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2249856).

1891280 is an abundant number, since it is smaller than the sum of its proper divisors (2608432).

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

1891280 is a wasteful number, since it uses less digits than its factorization.

1891280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 563 (or 557 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 1891280 is about 1375.2381611925. The cubic root of 1891280 is about 123.6664640458. Note that the first 3 decimals are identical.

The spelling of 1891280 in words is "one million, eight hundred ninety-one thousand, two hundred eighty".