1905137993 has 4 divisors (see below), whose sum is σ = 2078332368. Its totient is φ = 1731943620.

The previous prime is 1905137911. The next prime is 1905138007. The reversal of 1905137993 is 3997315091.

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 not a de Polignac number, because 1905137993 - 2¹⁰ = 1905136969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1905137093) 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, 86597171 + ... + 86597192.

It is an arithmetic number, because the mean of its divisors is an integer number (519583092).

Almost surely, 2^1905137993 is an apocalyptic number.

It is an amenable number.

1905137993 is a deficient number, since it is larger than the sum of its proper divisors (173194375).

1905137993 is a wasteful number, since it uses less digits than its factorization.

1905137993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173194374.

The product of its (nonzero) digits is 229635, while the sum is 47.

The square root of 1905137993 is about 43647.8864665862. The cubic root of 1905137993 is about 1239.6777676839.

The spelling of 1905137993 in words is "one billion, nine hundred five million, one hundred thirty-seven thousand, nine hundred ninety-three".