1978236449 has 16 divisors (see below), whose sum is σ = 2335441920. Its totient is φ = 1639759680.

The previous prime is 1978236427. The next prime is 1978236473. The reversal of 1978236449 is 9446328791.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1978236449 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1978236449.

It is not an unprimeable number, because it can be changed into a prime (1978236349) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 438047 + ... + 442539.

It is an arithmetic number, because the mean of its divisors is an integer number (145965120).

Almost surely, 2^1978236449 is an apocalyptic number.

It is an amenable number.

1978236449 is a deficient number, since it is larger than the sum of its proper divisors (357205471).

1978236449 is a wasteful number, since it uses less digits than its factorization.

1978236449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6560.

The product of its digits is 2612736, while the sum is 53.

The square root of 1978236449 is about 44477.3700773776. The cubic root of 1978236449 is about 1255.3343128241.

The spelling of 1978236449 in words is "one billion, nine hundred seventy-eight million, two hundred thirty-six thousand, four hundred forty-nine".