78204990 has 16 divisors (see below), whose sum is σ = 187692048. Its totient is φ = 20854656.

The previous prime is 78204983. The next prime is 78205019. The reversal of 78204990 is 9940287.

It is a super-2 number, since 2×78204990² = 12232040921800200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1303387 + ... + 1303446.

It is an arithmetic number, because the mean of its divisors is an integer number (11730753).

Almost surely, 2^78204990 is an apocalyptic number.

78204990 is an abundant number, since it is smaller than the sum of its proper divisors (109487058).

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

78204990 is a wasteful number, since it uses less digits than its factorization.

78204990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2606843.

The product of its (nonzero) digits is 36288, while the sum is 39.

The square root of 78204990 is about 8843.3585249044. The cubic root of 78204990 is about 427.6398366110.

The spelling of 78204990 in words is "seventy-eight million, two hundred four thousand, nine hundred ninety".