205620990 has 32 divisors (see below), whose sum is σ = 500860800. Its totient is φ = 54013344.

The previous prime is 205620901. The next prime is 205620997. The reversal of 205620990 is 99026502.

205620990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205620997) 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, 49140 + ... + 53159.

It is an arithmetic number, because the mean of its divisors is an integer number (15651900).

Almost surely, 2^205620990 is an apocalyptic number.

205620990 is an abundant number, since it is smaller than the sum of its proper divisors (295239810).

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

205620990 is a wasteful number, since it uses less digits than its factorization.

205620990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102376.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 205620990 is about 14339.4905767255. The cubic root of 205620990 is about 590.2316336491.

The spelling of 205620990 in words is "two hundred five million, six hundred twenty thousand, nine hundred ninety".