1591281 has 6 divisors (see below), whose sum is σ = 2298530. Its totient is φ = 1060848.

The previous prime is 1591277. The next prime is 1591313. The reversal of 1591281 is 1821951.

It can be written as a sum of positive squares in only one way, i.e., 1461681 + 129600 = 1209^2 + 360^2 .

It is not a de Polignac number, because 1591281 - 2² = 1591277 is a prime.

It is a super-2 number, since 2×1591281² = 5064350441922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1591211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 88396 + ... + 88413.

2^1591281 is an apocalyptic number.

It is an amenable number.

1591281 is a deficient number, since it is larger than the sum of its proper divisors (707249).

1591281 is a wasteful number, since it uses less digits than its factorization.

1591281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176815 (or 176812 counting only the distinct ones).

The product of its digits is 720, while the sum is 27.

The square root of 1591281 is about 1261.4598685650. The cubic root of 1591281 is about 116.7478681861.

The spelling of 1591281 in words is "one million, five hundred ninety-one thousand, two hundred eighty-one".