78021264 has 80 divisors (see below), whose sum is σ = 208812032. Its totient is φ = 25087104.

The previous prime is 78021263. The next prime is 78021329. The reversal of 78021264 is 46212087.

It is not an unprimeable number, because it can be changed into a prime (78021263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212409 + ... + 212775.

Almost surely, 2^78021264 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 78021264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104406016).

78021264 is an abundant number, since it is smaller than the sum of its proper divisors (130790768).

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

78021264 is a wasteful number, since it uses less digits than its factorization.

78021264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524 (or 518 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 78021264 is about 8832.9646212356. The cubic root of 78021264 is about 427.3046910584.

It can be divided in two parts, 780 and 21264, that multiplied together give a triangular number (16585920 = T₅₇₅₉).

The spelling of 78021264 in words is "seventy-eight million, twenty-one thousand, two hundred sixty-four".