1981980000 has 1080 divisors, whose sum is σ = 9528062544. Its totient is φ = 380160000.

The previous prime is 1981979983. The next prime is 1981980017. The reversal of 1981980000 is 891891.

It is an interprime number because it is at equal distance from previous prime (1981979983) and next prime (1981980017).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 152459994 + ... + 152460006.

Almost surely, 2^1981980000 is an apocalyptic number.

1981980000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1981980000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4764031272).

1981980000 is an abundant number, since it is smaller than the sum of its proper divisors (7546082544).

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

1981980000 is a wasteful number, since it uses less digits than its factorization.

1981980000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 1981980000 is about 44519.4339586657. The cubic root of 1981980000 is about 1256.1256652769.

It can be divided in two parts, 198 and 1980000, that multiplied together give a square (392040000 = 19800²).

The spelling of 1981980000 in words is "one billion, nine hundred eighty-one million, nine hundred eighty thousand".