78728372 has 6 divisors (see below), whose sum is σ = 137774658. Its totient is φ = 39364184.

The previous prime is 78728357. The next prime is 78728387. The reversal of 78728372 is 27382787.

It is an interprime number because it is at equal distance from previous prime (78728357) and next prime (78728387).

It can be written as a sum of positive squares in only one way, i.e., 66520336 + 12208036 = 8156^2 + 3494^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9841043 + ... + 9841050.

It is an arithmetic number, because the mean of its divisors is an integer number (22962443).

Almost surely, 2^78728372 is an apocalyptic number.

It is an amenable number.

78728372 is a deficient number, since it is larger than the sum of its proper divisors (59046286).

78728372 is a wasteful number, since it uses less digits than its factorization.

78728372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19682097 (or 19682095 counting only the distinct ones).

The product of its digits is 263424, while the sum is 44.

The square root of 78728372 is about 8872.9009912204. The cubic root of 78728372 is about 428.5917006072.

The spelling of 78728372 in words is "seventy-eight million, seven hundred twenty-eight thousand, three hundred seventy-two".