491561502838 has 8 divisors (see below), whose sum is σ = 842676862032. Its totient is φ = 210669215496.

The previous prime is 491561502829. The next prime is 491561502853. The reversal of 491561502838 is 838205165194.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×491561502838² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17555767945 + ... + 17555767972.

It is an arithmetic number, because the mean of its divisors is an integer number (105334607754).

Almost surely, 2^491561502838 is an apocalyptic number.

491561502838 is a deficient number, since it is larger than the sum of its proper divisors (351115359194).

491561502838 is a wasteful number, since it uses less digits than its factorization.

491561502838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35111535926.

The product of its (nonzero) digits is 2073600, while the sum is 52.

The spelling of 491561502838 in words is "four hundred ninety-one billion, five hundred sixty-one million, five hundred two thousand, eight hundred thirty-eight".