1331830921 has 8 divisors (see below), whose sum is σ = 1364827464. Its totient is φ = 1298858880.

The previous prime is 1331830919. The next prime is 1331830931. The reversal of 1331830921 is 1290381331.

It can be written as a sum of positive squares in 4 ways, for example, as 21752896 + 1310078025 = 4664^2 + 36195^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1331830921 - 2¹ = 1331830919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1331830931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156451 + ... + 164743.

It is an arithmetic number, because the mean of its divisors is an integer number (170603433).

Almost surely, 2^1331830921 is an apocalyptic number.

It is an amenable number.

1331830921 is a deficient number, since it is larger than the sum of its proper divisors (32996543).

1331830921 is an equidigital number, since it uses as much as digits as its factorization.

1331830921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12251.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 1331830921 is about 36494.2587402457. The cubic root of 1331830921 is about 1100.2288562396.

The spelling of 1331830921 in words is "one billion, three hundred thirty-one million, eight hundred thirty thousand, nine hundred twenty-one".