1129070821 has 4 divisors (see below), whose sum is σ = 1141757100. Its totient is φ = 1116384544.

The previous prime is 1129070807. The next prime is 1129070837. The reversal of 1129070821 is 1280709211.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1280709211 = 79 ⋅16211509.

It can be written as a sum of positive squares in 2 ways, for example, as 344510721 + 784560100 = 18561^2 + 28010^2 .

It is a cyclic number.

It is not a de Polignac number, because 1129070821 - 2⁷ = 1129070693 is a prime.

It is a super-2 number, since 2×1129070821² = 2549601837667228082, 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 (1129070321) 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, 6343006 + ... + 6343183.

It is an arithmetic number, because the mean of its divisors is an integer number (285439275).

Almost surely, 2^1129070821 is an apocalyptic number.

It is an amenable number.

1129070821 is a deficient number, since it is larger than the sum of its proper divisors (12686279).

1129070821 is an equidigital number, since it uses as much as digits as its factorization.

1129070821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12686278.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 1129070821 is about 33601.6490815555. The cubic root of 1129070821 is about 1041.2948679665.

The spelling of 1129070821 in words is "one billion, one hundred twenty-nine million, seventy thousand, eight hundred twenty-one".