1980156340 has 12 divisors (see below), whose sum is σ = 4158328356. Its totient is φ = 792062528.

The previous prime is 1980156323. The next prime is 1980156349. The reversal of 1980156340 is 436510891.

It can be written as a sum of positive squares in 2 ways, for example, as 884943504 + 1095212836 = 29748^2 + 33094^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1980156340.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1980156349) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49503889 + ... + 49503928.

It is an arithmetic number, because the mean of its divisors is an integer number (346527363).

Almost surely, 2^1980156340 is an apocalyptic number.

1980156340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1980156340 is an abundant number, since it is smaller than the sum of its proper divisors (2178172016).

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

1980156340 is a wasteful number, since it uses less digits than its factorization.

1980156340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99007826 (or 99007824 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 1980156340 is about 44498.9476280058. The cubic root of 1980156340 is about 1255.7402848194.

The spelling of 1980156340 in words is "one billion, nine hundred eighty million, one hundred fifty-six thousand, three hundred forty".