78606990 has 256 divisors, whose sum is σ = 276480000. Its totient is φ = 15396480.

The previous prime is 78606989. The next prime is 78607007. The reversal of 78606990 is 9960687.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 394911 + ... + 395109.

It is an arithmetic number, because the mean of its divisors is an integer number (1080000).

Almost surely, 2^78606990 is an apocalyptic number.

78606990 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 78606990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138240000).

78606990 is an abundant number, since it is smaller than the sum of its proper divisors (197873010).

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

78606990 is a wasteful number, since it uses less digits than its factorization.

78606990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 78606990 is about 8866.0583124633. The cubic root of 78606990 is about 428.3713222963.

The spelling of 78606990 in words is "seventy-eight million, six hundred six thousand, nine hundred ninety".