1478407991 has 4 divisors (see below), whose sum is σ = 1478490000. Its totient is φ = 1478325984.

The previous prime is 1478407969. The next prime is 1478408021. The reversal of 1478407991 is 1997048741.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1478407991 - 2¹⁸ = 1478145847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1478407291) 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, 866 + ... + 54383.

It is an arithmetic number, because the mean of its divisors is an integer number (369622500).

Almost surely, 2^1478407991 is an apocalyptic number.

1478407991 is a deficient number, since it is larger than the sum of its proper divisors (82009).

1478407991 is an equidigital number, since it uses as much as digits as its factorization.

1478407991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82008.

The product of its (nonzero) digits is 508032, while the sum is 50.

The square root of 1478407991 is about 38450.0714043550. The cubic root of 1478407991 is about 1139.1950794381.

The spelling of 1478407991 in words is "one billion, four hundred seventy-eight million, four hundred seven thousand, nine hundred ninety-one".