2131921481 has 2 divisors, whose sum is σ = 2131921482. Its totient is φ = 2131921480.

The previous prime is 2131921471. The next prime is 2131921489. The reversal of 2131921481 is 1841291312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1999878400 + 132043081 = 44720^2 + 11491^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2131921481 is a prime.

It is a super-2 number, since 2×2131921481² = 9090178402298466722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2131921489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1065960740 + 1065960741.

It is an arithmetic number, because the mean of its divisors is an integer number (1065960741).

Almost surely, 2^2131921481 is an apocalyptic number.

It is an amenable number.

2131921481 is a deficient number, since it is larger than the sum of its proper divisors (1).

2131921481 is an equidigital number, since it uses as much as digits as its factorization.

2131921481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 32.

The square root of 2131921481 is about 46172.7352557762. The cubic root of 2131921481 is about 1287.0351317117.

The spelling of 2131921481 in words is "two billion, one hundred thirty-one million, nine hundred twenty-one thousand, four hundred eighty-one".