1921587425 has 12 divisors (see below), whose sum is σ = 2383506300. Its totient is φ = 1536793920.

The previous prime is 1921587407. The next prime is 1921587449. The reversal of 1921587425 is 5247851291.

It can be written as a sum of positive squares in 6 ways, for example, as 1132096 + 1920455329 = 1064^2 + 43823^2 .

It is not a de Polignac number, because 1921587425 - 2⁶ = 1921587361 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 86351 + ... + 106299.

It is an arithmetic number, because the mean of its divisors is an integer number (198625525).

Almost surely, 2^1921587425 is an apocalyptic number.

It is an amenable number.

1921587425 is a deficient number, since it is larger than the sum of its proper divisors (461918875).

1921587425 is a wasteful number, since it uses less digits than its factorization.

1921587425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23812 (or 23807 counting only the distinct ones).

The product of its digits is 201600, while the sum is 44.

The square root of 1921587425 is about 43835.9147845691. The cubic root of 1921587425 is about 1243.2354426465.

The spelling of 1921587425 in words is "one billion, nine hundred twenty-one million, five hundred eighty-seven thousand, four hundred twenty-five".