1905125521 has 8 divisors (see below), whose sum is σ = 2066435840. Its totient is φ = 1745924112.

The previous prime is 1905125483. The next prime is 1905125531. The reversal of 1905125521 is 1255215091.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1905125521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1905125531) 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, 525345 + ... + 528958.

It is an arithmetic number, because the mean of its divisors is an integer number (258304480).

Almost surely, 2^1905125521 is an apocalyptic number.

It is an amenable number.

1905125521 is a deficient number, since it is larger than the sum of its proper divisors (161310319).

1905125521 is a wasteful number, since it uses less digits than its factorization.

1905125521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1054455.

The product of its (nonzero) digits is 4500, while the sum is 31.

The square root of 1905125521 is about 43647.7435957462. The cubic root of 1905125521 is about 1239.6750624914.

The spelling of 1905125521 in words is "one billion, nine hundred five million, one hundred twenty-five thousand, five hundred twenty-one".