206510125440 has 128 divisors (see below), whose sum is σ = 658917364320. Its totient is φ = 55013621760.

The previous prime is 206510125399. The next prime is 206510125441. The reversal of 206510125440 is 44521015602.

It is a tau number, because it is divible by the number of its divisors (128).

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 = 206510125398 and 206510125407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206510125441) 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, 1860300 + ... + 1968180.

Almost surely, 2^206510125440 is an apocalyptic number.

206510125440 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 206510125440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329458682160).

206510125440 is an abundant number, since it is smaller than the sum of its proper divisors (452407238880).

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

206510125440 is a wasteful number, since it uses less digits than its factorization.

206510125440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108900 (or 108888 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The spelling of 206510125440 in words is "two hundred six billion, five hundred ten million, one hundred twenty-five thousand, four hundred forty".