1151531 has 4 divisors (see below), whose sum is σ = 1173312. Its totient is φ = 1129752.

The previous prime is 1151519. The next prime is 1151537. The reversal of 1151531 is 1351511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1351511 = 7 ⋅193073.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1151531 is a prime.

It is a super-2 number, since 2×1151531² = 2652047287922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1151537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10811 + ... + 10916.

It is an arithmetic number, because the mean of its divisors is an integer number (293328).

2^1151531 is an apocalyptic number.

1151531 is a deficient number, since it is larger than the sum of its proper divisors (21781).

1151531 is an equidigital number, since it uses as much as digits as its factorization.

1151531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21780.

The product of its digits is 75, while the sum is 17.

The square root of 1151531 is about 1073.0941244830. The cubic root of 1151531 is about 104.8154278222.

The spelling of 1151531 in words is "one million, one hundred fifty-one thousand, five hundred thirty-one".