1881212797 has 4 divisors (see below), whose sum is σ = 1898471740. Its totient is φ = 1863953856.

The previous prime is 1881212789. The next prime is 1881212807. The reversal of 1881212797 is 7972121881.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 954253881 + 926958916 = 30891^2 + 30446^2 .

It is a cyclic number.

It is not a de Polignac number, because 1881212797 - 2³ = 1881212789 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 (1881212747) 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, 8629308 + ... + 8629525.

It is an arithmetic number, because the mean of its divisors is an integer number (474617935).

Almost surely, 2^1881212797 is an apocalyptic number.

It is an amenable number.

1881212797 is a deficient number, since it is larger than the sum of its proper divisors (17258943).

1881212797 is a wasteful number, since it uses less digits than its factorization.

1881212797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17258942.

The product of its digits is 112896, while the sum is 46.

The square root of 1881212797 is about 43372.9500610692. The cubic root of 1881212797 is about 1234.4664978649.

The spelling of 1881212797 in words is "one billion, eight hundred eighty-one million, two hundred twelve thousand, seven hundred ninety-seven".