1251531 has 10 divisors (see below), whose sum is σ = 1869692. Its totient is φ = 834300.

The previous prime is 1251529. The next prime is 1251533. The reversal of 1251531 is 1351521.

It is an interprime number because it is at equal distance from previous prime (1251529) and next prime (1251533).

It is not a de Polignac number, because 1251531 - 2¹ = 1251529 is a prime.

It is a super-2 number, since 2×1251531² = 3132659687922, which contains 22 as substring.

It is a Duffinian number.

1251531 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1251533) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 7645 + ... + 7806.

2^1251531 is an apocalyptic number.

1251531 is a deficient number, since it is larger than the sum of its proper divisors (618161).

1251531 is an equidigital number, since it uses as much as digits as its factorization.

1251531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15463 (or 15454 counting only the distinct ones).

The product of its digits is 150, while the sum is 18.

The square root of 1251531 is about 1118.7184632427. The cubic root of 1251531 is about 107.7656957520.

The spelling of 1251531 in words is "one million, two hundred fifty-one thousand, five hundred thirty-one".