1978247913 has 8 divisors (see below), whose sum is σ = 2663779776. Its totient is φ = 1305774000.

The previous prime is 1978247911. The next prime is 1978247933. The reversal of 1978247913 is 3197428791.

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

It is not a de Polignac number, because 1978247913 - 2¹ = 1978247911 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1978247911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3264133 + ... + 3264738.

It is an arithmetic number, because the mean of its divisors is an integer number (332972472).

Almost surely, 2^1978247913 is an apocalyptic number.

It is an amenable number.

1978247913 is a deficient number, since it is larger than the sum of its proper divisors (685531863).

1978247913 is a wasteful number, since it uses less digits than its factorization.

1978247913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6528975.

The product of its digits is 762048, while the sum is 51.

The square root of 1978247913 is about 44477.4989517171. The cubic root of 1978247913 is about 1255.3367377322.

The spelling of 1978247913 in words is "one billion, nine hundred seventy-eight million, two hundred forty-seven thousand, nine hundred thirteen".