7999990 has 8 divisors (see below), whose sum is σ = 14400000. Its totient is φ = 3199992.

The previous prime is 7999963. The next prime is 7999993. The reversal of 7999990 is 999997.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7999993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 399990 + ... + 400009.

It is an arithmetic number, because the mean of its divisors is an integer number (1800000).

Almost surely, 2^7999990 is an apocalyptic number.

7999990 is a deficient number, since it is larger than the sum of its proper divisors (6400010).

7999990 is a wasteful number, since it uses less digits than its factorization.

7999990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800006.

The product of its (nonzero) digits is 413343, while the sum is 52.

The square root of 7999990 is about 2828.4253569787. The cubic root of 7999990 is about 199.9999166666. Note that the first 4 decimals are identical.

It can be divided in two parts, 79999 and 90, that added together give a square (80089 = 283²).

The spelling of 7999990 in words is "seven million, nine hundred ninety-nine thousand, nine hundred ninety".