1881551 has 24 divisors (see below), whose sum is σ = 2407680. Its totient is φ = 1460592.

The previous prime is 1881533. The next prime is 1881559. The reversal of 1881551 is 1551881.

1881551 is nontrivially palindromic in base 11.

It is a de Polignac number, because none of the positive numbers 2^k-1881551 is a prime.

1881551 is a modest number, since divided by 1551 gives 188 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1881559) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40010 + ... + 40056.

It is an arithmetic number, because the mean of its divisors is an integer number (100320).

2^1881551 is an apocalyptic number.

1881551 is a deficient number, since it is larger than the sum of its proper divisors (526129).

1881551 is a wasteful number, since it uses less digits than its factorization.

1881551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 116 counting only the distinct ones).

The product of its digits is 1600, while the sum is 29.

The square root of 1881551 is about 1371.6963949796. The cubic root of 1881551 is about 123.4540470580.

The spelling of 1881551 in words is "one million, eight hundred eighty-one thousand, five hundred fifty-one".