205922640 has 240 divisors, whose sum is σ = 802698624. Its totient is φ = 42746880.

The previous prime is 205922621. The next prime is 205922663. The reversal of 205922640 is 46229502.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 205922598 and 205922607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 202774 + ... + 203786.

Almost surely, 2^205922640 is an apocalyptic number.

205922640 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 205922640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401349312).

205922640 is an abundant number, since it is smaller than the sum of its proper divisors (596775984).

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

205922640 is a wasteful number, since it uses less digits than its factorization.

205922640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058 (or 1041 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 205922640 is about 14350.0048780480. The cubic root of 205922640 is about 590.5201197270.

It can be divided in two parts, 20592 and 2640, that added together give a palindrome (23232).

The spelling of 205922640 in words is "two hundred five million, nine hundred twenty-two thousand, six hundred forty".