649116878 has 4 divisors (see below), whose sum is σ = 973675320. Its totient is φ = 324558438.

The previous prime is 649116877. The next prime is 649116901. The reversal of 649116878 is 878611946.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649116877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 162279218 + ... + 162279221.

It is an arithmetic number, because the mean of its divisors is an integer number (243418830).

Almost surely, 2^649116878 is an apocalyptic number.

649116878 is a deficient number, since it is larger than the sum of its proper divisors (324558442).

649116878 is a wasteful number, since it uses less digits than its factorization.

649116878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324558441.

The product of its digits is 580608, while the sum is 50.

The square root of 649116878 is about 25477.7722338512. The cubic root of 649116878 is about 865.8466225070.

The spelling of 649116878 in words is "six hundred forty-nine million, one hundred sixteen thousand, eight hundred seventy-eight".