6978477649 has 12 divisors (see below), whose sum is σ = 8260602868. Its totient is φ = 5856063840.

The previous prime is 6978477601. The next prime is 6978477659. The reversal of 6978477649 is 9467748796.

It can be written as a sum of positive squares in 2 ways, for example, as 418611600 + 6559866049 = 20460^2 + 80993^2 .

It is not a de Polignac number, because 6978477649 - 2⁷ = 6978477521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6978477659) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2216634 + ... + 2219779.

Almost surely, 2^6978477649 is an apocalyptic number.

It is an amenable number.

6978477649 is a deficient number, since it is larger than the sum of its proper divisors (1282125219).

6978477649 is a wasteful number, since it uses less digits than its factorization.

6978477649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4436448 (or 4436437 counting only the distinct ones).

The product of its digits is 128024064, while the sum is 67.

The square root of 6978477649 is about 83537.2829878971. The cubic root of 6978477649 is about 1910.9686568948.

The spelling of 6978477649 in words is "six billion, nine hundred seventy-eight million, four hundred seventy-seven thousand, six hundred forty-nine".