1971851028 has 24 divisors (see below), whose sum is σ = 5258269632. Its totient is φ = 563385984.

The previous prime is 1971851023. The next prime is 1971851051. The reversal of 1971851028 is 8201581791.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1971851023) 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 7 ways as a sum of consecutive naturals, for example, 11737125 + ... + 11737292.

It is an arithmetic number, because the mean of its divisors is an integer number (219094568).

Almost surely, 2^1971851028 is an apocalyptic number.

It is an amenable number.

1971851028 is an abundant number, since it is smaller than the sum of its proper divisors (3286418604).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1971851028 is a wasteful number, since it uses less digits than its factorization.

1971851028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23474431 (or 23474429 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 42.

The square root of 1971851028 is about 44405.5292503085. The cubic root of 1971851028 is about 1253.9821862557.

The spelling of 1971851028 in words is "one billion, nine hundred seventy-one million, eight hundred fifty-one thousand, twenty-eight".