1898881938 has 18 divisors (see below), whose sum is σ = 4114644807. Its totient is φ = 632899020.

The previous prime is 1898881903. The next prime is 1898881939. The reversal of 1898881938 is 8391888981.

It can be written as a sum of positive squares in only one way, i.e., 949440969 + 949440969 = 30813^2 + 30813^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=30813.

It is a super-2 number, since 2×1898881938² = 7211505228925271688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1898881939) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 179743 + ... + 190013.

Almost surely, 2^1898881938 is an apocalyptic number.

1898881938 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1898881938 is an abundant number, since it is smaller than the sum of its proper divisors (2215762869).

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

1898881938 is an frugal number, since it uses more digits than its factorization.

1898881938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20550 (or 10276 counting only the distinct ones).

The product of its digits is 7962624, while the sum is 63.

The square root of 1898881938 is about 43576.1624974022. The cubic root of 1898881938 is about 1238.3193364385.

The spelling of 1898881938 in words is "one billion, eight hundred ninety-eight million, eight hundred eighty-one thousand, nine hundred thirty-eight".