1251987 has 12 divisors (see below), whose sum is σ = 1835400. Its totient is φ = 758560.

The previous prime is 1251983. The next prime is 1252021. The reversal of 1251987 is 7891521.

It is not a de Polignac number, because 1251987 - 2² = 1251983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1251983) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1362 + ... + 2087.

It is an arithmetic number, because the mean of its divisors is an integer number (152950).

2^1251987 is an apocalyptic number.

1251987 is a deficient number, since it is larger than the sum of its proper divisors (583413).

1251987 is a wasteful number, since it uses less digits than its factorization.

1251987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3474 (or 3463 counting only the distinct ones).

The product of its digits is 5040, while the sum is 33.

The square root of 1251987 is about 1118.9222493096. The cubic root of 1251987 is about 107.7787824409.

It can be divided in two parts, 125 and 1987, that added together give a palindrome (2112).

The spelling of 1251987 in words is "one million, two hundred fifty-one thousand, nine hundred eighty-seven".