8378778731 has 4 divisors (see below), whose sum is σ = 8427211152. Its totient is φ = 8330346312.

The previous prime is 8378778697. The next prime is 8378778787. The reversal of 8378778731 is 1378778738.

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

It is a cyclic number.

It is not a de Polignac number, because 8378778731 - 2¹⁴ = 8378762347 is a prime.

It is a super-2 number, since 2×8378778731² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8378778791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24215951 + ... + 24216296.

It is an arithmetic number, because the mean of its divisors is an integer number (2106802788).

Almost surely, 2^8378778731 is an apocalyptic number.

8378778731 is a deficient number, since it is larger than the sum of its proper divisors (48432421).

8378778731 is a wasteful number, since it uses less digits than its factorization.

8378778731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48432420.

The product of its digits is 11063808, while the sum is 59.

The square root of 8378778731 is about 91535.6691732791. The cubic root of 8378778731 is about 2031.0794271397.

The spelling of 8378778731 in words is "eight billion, three hundred seventy-eight million, seven hundred seventy-eight thousand, seven hundred thirty-one".