205979340 has 72 divisors (see below), whose sum is σ = 670913712. Its totient is φ = 47080320.

The previous prime is 205979339. The next prime is 205979341. The reversal of 205979340 is 43979502.

It is an interprime number because it is at equal distance from previous prime (205979339) and next prime (205979341).

It is not an unprimeable number, because it can be changed into a prime (205979341) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32091 + ... + 37970.

It is an arithmetic number, because the mean of its divisors is an integer number (9318246).

Almost surely, 2^205979340 is an apocalyptic number.

205979340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205979340 is an abundant number, since it is smaller than the sum of its proper divisors (464934372).

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

205979340 is a wasteful number, since it uses less digits than its factorization.

205979340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70087 (or 70078 counting only the distinct ones).

The product of its (nonzero) digits is 68040, while the sum is 39.

The square root of 205979340 is about 14351.9803511571. The cubic root of 205979340 is about 590.5743138945.

The spelling of 205979340 in words is "two hundred five million, nine hundred seventy-nine thousand, three hundred forty".