981537506 has 4 divisors (see below), whose sum is σ = 1472306262. Its totient is φ = 490768752.

The previous prime is 981537481. The next prime is 981537521. The reversal of 981537506 is 605735189.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 605735189 = 41 ⋅14774029.

It can be written as a sum of positive squares in only one way, i.e., 828000625 + 153536881 = 28775^2 + 12391^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245384375 + ... + 245384378.

Almost surely, 2^981537506 is an apocalyptic number.

981537506 is a deficient number, since it is larger than the sum of its proper divisors (490768756).

981537506 is a wasteful number, since it uses less digits than its factorization.

981537506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 490768755.

The product of its (nonzero) digits is 226800, while the sum is 44.

The square root of 981537506 is about 31329.4989746086. The cubic root of 981537506 is about 993.8075682748.

The spelling of 981537506 in words is "nine hundred eighty-one million, five hundred thirty-seven thousand, five hundred six".