1981500156 has 36 divisors (see below), whose sum is σ = 5032549704. Its totient is φ = 657367200.

The previous prime is 1981500133. The next prime is 1981500167. The reversal of 1981500156 is 6510051891.

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a self number, because there is not a number n which added to its sum of digits gives 1981500156.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 122835 + ... + 138026.

Almost surely, 2^1981500156 is an apocalyptic number.

It is an amenable number.

1981500156 is an abundant number, since it is smaller than the sum of its proper divisors (3051049548).

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

1981500156 is a wasteful number, since it uses less digits than its factorization.

1981500156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261082 (or 261077 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 36.

The square root of 1981500156 is about 44514.0444803660. The cubic root of 1981500156 is about 1256.0242863507.

The spelling of 1981500156 in words is "one billion, nine hundred eighty-one million, five hundred thousand, one hundred fifty-six".