491490146778 has 16 divisors (see below), whose sum is σ = 1034716098720. Its totient is φ = 155207414736.

The previous prime is 491490146687. The next prime is 491490146803. The reversal of 491490146778 is 877641094194.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2155658425 + ... + 2155658652.

It is an arithmetic number, because the mean of its divisors is an integer number (64669756170).

Almost surely, 2^491490146778 is an apocalyptic number.

491490146778 is an abundant number, since it is smaller than the sum of its proper divisors (543225951942).

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

491490146778 is a wasteful number, since it uses less digits than its factorization.

491490146778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4311317101.

The product of its (nonzero) digits is 12192768, while the sum is 60.

The spelling of 491490146778 in words is "four hundred ninety-one billion, four hundred ninety million, one hundred forty-six thousand, seven hundred seventy-eight".