2251881 has 14 divisors (see below), whose sum is σ = 3377370. Its totient is φ = 1500768.

The previous prime is 2251877. The next prime is 2251891. The reversal of 2251881 is 1881522.

It can be written as a sum of positive squares in only one way, i.e., 2205225 + 46656 = 1485^2 + 216^2 .

It is not a de Polignac number, because 2251881 - 2² = 2251877 is a prime.

It is a super-2 number, since 2×2251881² = 10141936076322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

2251881 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2251841) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 816 + ... + 2273.

2^2251881 is an apocalyptic number.

It is an amenable number.

2251881 is a deficient number, since it is larger than the sum of its proper divisors (1125489).

2251881 is an frugal number, since it uses more digits than its factorization.

2251881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3107 (or 3092 counting only the distinct ones).

The product of its digits is 1280, while the sum is 27.

The square root of 2251881 is about 1500.6268690117. The cubic root of 2251881 is about 131.0735752029.

The spelling of 2251881 in words is "two million, two hundred fifty-one thousand, eight hundred eighty-one".