1872421945 has 8 divisors (see below), whose sum is σ = 2248541640. Its totient is φ = 1496847360.

The previous prime is 1872421921. The next prime is 1872421949. The reversal of 1872421945 is 5491242781.

It can be written as a sum of positive squares in 4 ways, for example, as 443355136 + 1429066809 = 21056^2 + 37803^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1872421945 - 2²⁷ = 1738204217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1872421949) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128680 + ... + 142489.

It is an arithmetic number, because the mean of its divisors is an integer number (281067705).

Almost surely, 2^1872421945 is an apocalyptic number.

It is an amenable number.

1872421945 is a deficient number, since it is larger than the sum of its proper divisors (376119695).

1872421945 is a wasteful number, since it uses less digits than its factorization.

1872421945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272555.

The product of its digits is 161280, while the sum is 43.

The square root of 1872421945 is about 43271.4911344640. The cubic root of 1872421945 is about 1232.5406196883.

The spelling of 1872421945 in words is "one billion, eight hundred seventy-two million, four hundred twenty-one thousand, nine hundred forty-five".