1921975057 has 4 divisors (see below), whose sum is σ = 1925142016. Its totient is φ = 1918808100.

The previous prime is 1921975037. The next prime is 1921975063. The reversal of 1921975057 is 7505791291.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1921975057 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1921974998 and 1921975016.

It is not an unprimeable number, because it can be changed into a prime (1921975037) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1582569 + ... + 1583782.

It is an arithmetic number, because the mean of its divisors is an integer number (481285504).

Almost surely, 2^1921975057 is an apocalyptic number.

It is an amenable number.

1921975057 is a deficient number, since it is larger than the sum of its proper divisors (3166959).

1921975057 is an equidigital number, since it uses as much as digits as its factorization.

1921975057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3166958.

The product of its (nonzero) digits is 198450, while the sum is 46.

The square root of 1921975057 is about 43840.3359590229. The cubic root of 1921975057 is about 1243.3190342009.

The spelling of 1921975057 in words is "one billion, nine hundred twenty-one million, nine hundred seventy-five thousand, fifty-seven".