1905648981523 has 16 divisors (see below), whose sum is σ = 2298860554240. Its totient is φ = 1547444246760.

The previous prime is 1905648981503. The next prime is 1905648981547. The reversal of 1905648981523 is 3251898465091.

It is a de Polignac number, because none of the positive numbers 2^k-1905648981523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1905648981503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19797123 + ... + 19893148.

It is an arithmetic number, because the mean of its divisors is an integer number (143678784640).

Almost surely, 2^{1905648981523} is an apocalyptic number.

1905648981523 is a deficient number, since it is larger than the sum of its proper divisors (393211572717).

1905648981523 is an frugal number, since it uses more digits than its factorization.

1905648981523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39690335 (or 39690297 counting only the distinct ones).

The product of its (nonzero) digits is 18662400, while the sum is 61.

The spelling of 1905648981523 in words is "one trillion, nine hundred five billion, six hundred forty-eight million, nine hundred eighty-one thousand, five hundred twenty-three".