78321898736640 has 2112 divisors, whose sum is σ = 322136440045056. Its totient is φ = 18076048293888.

The previous prime is 78321898736603. The next prime is 78321898736689. The reversal of 78321898736640 is 4663789812387.

78321898736640 is a `hidden beast` number, since 7 + 8 + 3 + 2 + 189 + 87 + 366 + 4 + 0 = 666.

It is a super-2 number, since 2×78321898736640² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 121806996159 + ... + 121806996801.

Almost surely, 2^{78321898736640} 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 78321898736640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161068220022528).

78321898736640 is an abundant number, since it is smaller than the sum of its proper divisors (243814541308416).

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

78321898736640 is a wasteful number, since it uses less digits than its factorization.

78321898736640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1156 (or 1126 counting only the distinct ones).

The product of its (nonzero) digits is 585252864, while the sum is 72.

The spelling of 78321898736640 in words is "seventy-eight trillion, three hundred twenty-one billion, eight hundred ninety-eight million, seven hundred thirty-six thousand, six hundred forty".