2820129381 has 12 divisors (see below), whose sum is σ = 4183615852. Its totient is φ = 1829272896.

The previous prime is 2820129379. The next prime is 2820129409. The reversal of 2820129381 is 1839210282.

It can be written as a sum of positive squares in 2 ways, for example, as 996412356 + 1823717025 = 31566^2 + 42705^2 .

It is not a de Polignac number, because 2820129381 - 2¹ = 2820129379 is a prime.

It is a super-2 number, since 2×2820129381² = 15906259451158886322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2820129581) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4234096 + ... + 4234761.

Almost surely, 2^2820129381 is an apocalyptic number.

It is an amenable number.

2820129381 is a deficient number, since it is larger than the sum of its proper divisors (1363486471).

2820129381 is a wasteful number, since it uses less digits than its factorization.

2820129381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8468900 (or 8468897 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 2820129381 is about 53104.8903680254. The cubic root of 2820129381 is about 1412.8292504817.

The spelling of 2820129381 in words is "two billion, eight hundred twenty million, one hundred twenty-nine thousand, three hundred eighty-one".