1921163149 has 4 divisors (see below), whose sum is σ = 2034172764. Its totient is φ = 1808153536.

The previous prime is 1921163147. The next prime is 1921163161. The reversal of 1921163149 is 9413611291.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9413611291 = 7 ⋅1344801613.

It can be written as a sum of positive squares in 2 ways, for example, as 1506837124 + 414326025 = 38818^2 + 20355^2 .

It is a cyclic number.

It is not a de Polignac number, because 1921163149 - 2¹ = 1921163147 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921163147) 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, 56504782 + ... + 56504815.

It is an arithmetic number, because the mean of its divisors is an integer number (508543191).

Almost surely, 2^1921163149 is an apocalyptic number.

It is an amenable number.

1921163149 is a deficient number, since it is larger than the sum of its proper divisors (113009615).

1921163149 is a wasteful number, since it uses less digits than its factorization.

1921163149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113009614.

The product of its digits is 11664, while the sum is 37.

The square root of 1921163149 is about 43831.0751522250. The cubic root of 1921163149 is about 1243.1439360480.

The spelling of 1921163149 in words is "one billion, nine hundred twenty-one million, one hundred sixty-three thousand, one hundred forty-nine".