491940538 has 4 divisors (see below), whose sum is σ = 737910810. Its totient is φ = 245970268.

The previous prime is 491940529. The next prime is 491940569. The reversal of 491940538 is 835049194.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 410994529 + 80946009 = 20273^2 + 8997^2 .

It is a junction number, because it is equal to n+sod(n) for n = 491940494 and 491940503.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122985133 + ... + 122985136.

Almost surely, 2^491940538 is an apocalyptic number.

491940538 is a deficient number, since it is larger than the sum of its proper divisors (245970272).

491940538 is a wasteful number, since it uses less digits than its factorization.

491940538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245970271.

The product of its (nonzero) digits is 155520, while the sum is 43.

The square root of 491940538 is about 22179.7325953222. The cubic root of 491940538 is about 789.4128725200.

The spelling of 491940538 in words is "four hundred ninety-one million, nine hundred forty thousand, five hundred thirty-eight".