1251881 has 2 divisors, whose sum is σ = 1251882. Its totient is φ = 1251880.

The previous prime is 1251871. The next prime is 1251907. The reversal of 1251881 is 1881521.

It is an a-pointer prime, because the next prime (1251907) can be obtained adding 1251881 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 774400 + 477481 = 880^2 + 691^2 .

It is an emirp because it is prime and its reverse (1881521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1251881 - 2¹⁴ = 1235497 is a prime.

It is a super-2 number, since 2×1251881² = 3134412076322, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1251881.

It is not a weakly prime, because it can be changed into another prime (1251841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625940 + 625941.

It is an arithmetic number, because the mean of its divisors is an integer number (625941).

2^1251881 is an apocalyptic number.

It is an amenable number.

1251881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251881 is an equidigital number, since it uses as much as digits as its factorization.

1251881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 640, while the sum is 26.

The square root of 1251881 is about 1118.8748812982. The cubic root of 1251881 is about 107.7757406432.

Adding to 1251881 its product of digits (640), we get a palindrome (1252521).

The spelling of 1251881 in words is "one million, two hundred fifty-one thousand, eight hundred eighty-one".