205421628 has 12 divisors (see below), whose sum is σ = 479317160. Its totient is φ = 68473872.

The previous prime is 205421569. The next prime is 205421633. The reversal of 205421628 is 826124502.

It is a tau number, because it is divible by the number of its divisors (12).

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 205421595 and 205421604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8559223 + ... + 8559246.

Almost surely, 2^205421628 is an apocalyptic number.

It is an amenable number.

205421628 is an abundant number, since it is smaller than the sum of its proper divisors (273895532).

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

205421628 is a wasteful number, since it uses less digits than its factorization.

205421628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17118476 (or 17118474 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 205421628 is about 14332.5373887529. The cubic root of 205421628 is about 590.0408168640.

The spelling of 205421628 in words is "two hundred five million, four hundred twenty-one thousand, six hundred twenty-eight".