1021881539 has 16 divisors (see below), whose sum is σ = 1185696960. Its totient is φ = 862617600.

The previous prime is 1021881463. The next prime is 1021881557. The reversal of 1021881539 is 9351881201.

It is a cyclic number.

It is not a de Polignac number, because 1021881539 - 2²⁰ = 1020832963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1021881589) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 132707 + ... + 140195.

It is an arithmetic number, because the mean of its divisors is an integer number (74106060).

Almost surely, 2^1021881539 is an apocalyptic number.

1021881539 is a deficient number, since it is larger than the sum of its proper divisors (163815421).

1021881539 is a wasteful number, since it uses less digits than its factorization.

1021881539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7790.

The product of its (nonzero) digits is 17280, while the sum is 38.

The square root of 1021881539 is about 31966.8819092510. The cubic root of 1021881539 is about 1007.2412835771.

The spelling of 1021881539 in words is "one billion, twenty-one million, eight hundred eighty-one thousand, five hundred thirty-nine".