1981800428 has 48 divisors (see below), whose sum is σ = 3660733440. Its totient is φ = 936950784.

The previous prime is 1981800427. The next prime is 1981800439. The reversal of 1981800428 is 8240081891.

It is not an unprimeable number, because it can be changed into a prime (1981800421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4243451 + ... + 4243917.

It is an arithmetic number, because the mean of its divisors is an integer number (76265280).

Almost surely, 2^1981800428 is an apocalyptic number.

It is an amenable number.

1981800428 is a deficient number, since it is larger than the sum of its proper divisors (1678933012).

1981800428 is a wasteful number, since it uses less digits than its factorization.

1981800428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926 (or 924 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 41.

The square root of 1981800428 is about 44517.4171308264. The cubic root of 1981800428 is about 1256.0877281617.

The spelling of 1981800428 in words is "one billion, nine hundred eighty-one million, eight hundred thousand, four hundred twenty-eight".