1871638461 has 32 divisors (see below), whose sum is σ = 3456998400. Its totient is φ = 972278640.

The previous prime is 1871638411. The next prime is 1871638469. The reversal of 1871638461 is 1648361781.

1871638461 is a `hidden beast` number, since 1 + 8 + 7 + 1 + 638 + 4 + 6 + 1 = 666.

It is not a de Polignac number, because 1871638461 - 2¹³ = 1871630269 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1871638469) 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 31 ways as a sum of consecutive naturals, for example, 448051 + ... + 452208.

It is an arithmetic number, because the mean of its divisors is an integer number (108031200).

Almost surely, 2^1871638461 is an apocalyptic number.

1871638461 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1871638461 is a deficient number, since it is larger than the sum of its proper divisors (1585359939).

1871638461 is a wasteful number, since it uses less digits than its factorization.

1871638461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900286 (or 900280 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 1871638461 is about 43262.4370672758. The cubic root of 1871638461 is about 1232.3686836246.

The spelling of 1871638461 in words is "one billion, eight hundred seventy-one million, six hundred thirty-eight thousand, four hundred sixty-one".