1491419778 has 8 divisors (see below), whose sum is σ = 2982839568. Its totient is φ = 497139924.

The previous prime is 1491419771. The next prime is 1491419789. The reversal of 1491419778 is 8779141941.

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

1491419778 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 1491419778.

It is not an unprimeable number, because it can be changed into a prime (1491419771) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124284976 + ... + 124284987.

It is an arithmetic number, because the mean of its divisors is an integer number (372854946).

Almost surely, 2^1491419778 is an apocalyptic number.

1491419778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1491419778 is a wasteful number, since it uses less digits than its factorization.

1491419778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248569968.

The product of its digits is 508032, while the sum is 51.

The square root of 1491419778 is about 38618.9044122176. The cubic root of 1491419778 is about 1142.5274226317.

The spelling of 1491419778 in words is "one billion, four hundred ninety-one million, four hundred nineteen thousand, seven hundred seventy-eight".