78297794440 has 64 divisors (see below), whose sum is σ = 181110504960. Its totient is φ = 30449644800.

The previous prime is 78297794437. The next prime is 78297794479. The reversal of 78297794440 is 4449779287.

It is a super-2 number, since 2×78297794440² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 145974 + ... + 421786.

It is an arithmetic number, because the mean of its divisors is an integer number (2829851640).

Almost surely, 2^78297794440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78297794440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90555252480).

78297794440 is an abundant number, since it is smaller than the sum of its proper divisors (102812710520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78297794440 is a wasteful number, since it uses less digits than its factorization.

78297794440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276022 (or 276018 counting only the distinct ones).

The product of its (nonzero) digits is 28449792, while the sum is 61.

The spelling of 78297794440 in words is "seventy-eight billion, two hundred ninety-seven million, seven hundred ninety-four thousand, four hundred forty".