205515420 has 96 divisors (see below), whose sum is σ = 632814336. Its totient is φ = 49420800.

The previous prime is 205515413. The next prime is 205515421. The reversal of 205515420 is 24515502.

It is a happy number.

205515420 is digitally balanced in base 3, 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 (205515421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 85272 + ... + 87648.

It is an arithmetic number, because the mean of its divisors is an integer number (6591816).

Almost surely, 2^205515420 is an apocalyptic number.

205515420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205515420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (316407168).

205515420 is an abundant number, since it is smaller than the sum of its proper divisors (427298916).

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

205515420 is a wasteful number, since it uses less digits than its factorization.

205515420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2531 (or 2529 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 205515420 is about 14335.8090110046. The cubic root of 205515420 is about 590.1306040469.

The spelling of 205515420 in words is "two hundred five million, five hundred fifteen thousand, four hundred twenty".