1331531023 has 4 divisors (see below), whose sum is σ = 1349771248. Its totient is φ = 1313290800.

The previous prime is 1331531021. The next prime is 1331531053. The reversal of 1331531023 is 3201351331.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3201351331 = 1373 ⋅2331647.

It is a cyclic number.

It is not a de Polignac number, because 1331531023 - 2¹ = 1331531021 is a prime.

It is a super-2 number, since 2×1331531023² = 3545949730422853058, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1331530985 and 1331531003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331531021) 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, 9120003 + ... + 9120148.

It is an arithmetic number, because the mean of its divisors is an integer number (337442812).

Almost surely, 2^1331531023 is an apocalyptic number.

1331531023 is a deficient number, since it is larger than the sum of its proper divisors (18240225).

1331531023 is an equidigital number, since it uses as much as digits as its factorization.

1331531023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18240224.

The product of its (nonzero) digits is 810, while the sum is 22.

The square root of 1331531023 is about 36490.1496708358. The cubic root of 1331531023 is about 1100.1462678776.

Adding to 1331531023 its reverse (3201351331), we get a palindrome (4532882354).

The spelling of 1331531023 in words is "one billion, three hundred thirty-one million, five hundred thirty-one thousand, twenty-three".