1898889778840 has 32 divisors (see below), whose sum is σ = 4273077473280. Its totient is φ = 759453605632.

The previous prime is 1898889778787. The next prime is 1898889778847. The reversal of 1898889778840 is 488779888981.

It is a super-2 number, since 2×1898889778840² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1898889778847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2896024 + ... + 3490663.

It is an arithmetic number, because the mean of its divisors is an integer number (133533671040).

Almost surely, 2^{1898889778840} is an apocalyptic number.

1898889778840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1898889778840 is an abundant number, since it is smaller than the sum of its proper divisors (2374187694440).

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

1898889778840 is a wasteful number, since it uses less digits than its factorization.

1898889778840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6394131 (or 6394127 counting only the distinct ones).

The product of its (nonzero) digits is 4161798144, while the sum is 85.

The spelling of 1898889778840 in words is "one trillion, eight hundred ninety-eight billion, eight hundred eighty-nine million, seven hundred seventy-eight thousand, eight hundred forty".