1881645 has 32 divisors (see below), whose sum is σ = 3276288. Its totient is φ = 918528.

The previous prime is 1881641. The next prime is 1881697. The reversal of 1881645 is 5461881.

It is not a de Polignac number, because 1881645 - 2² = 1881641 is a prime.

It is a super-3 number, since 3×1881645³ = 19986388591297233375, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1881641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11907 + ... + 12063.

It is an arithmetic number, because the mean of its divisors is an integer number (102384).

2^1881645 is an apocalyptic number.

1881645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1881645 is a deficient number, since it is larger than the sum of its proper divisors (1394643).

1881645 is a wasteful number, since it uses less digits than its factorization.

1881645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229.

The product of its digits is 7680, while the sum is 33.

The square root of 1881645 is about 1371.7306586936. The cubic root of 1881645 is about 123.4561028951.

The spelling of 1881645 in words is "one million, eight hundred eighty-one thousand, six hundred forty-five".