640055361 has 16 divisors (see below), whose sum is σ = 931415040. Its totient is φ = 387735120.

The previous prime is 640055333. The next prime is 640055363. The reversal of 640055361 is 163550046.

It is not a de Polignac number, because 640055361 - 2¹⁴ = 640038977 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (640055363) 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, 127660 + ... + 132578.

It is an arithmetic number, because the mean of its divisors is an integer number (58213440).

Almost surely, 2^640055361 is an apocalyptic number.

It is an amenable number.

640055361 is a deficient number, since it is larger than the sum of its proper divisors (291359679).

640055361 is a wasteful number, since it uses less digits than its factorization.

640055361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8876.

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 640055361 is about 25299.3154255209. The cubic root of 640055361 is about 861.7987235586.

The spelling of 640055361 in words is "six hundred forty million, fifty-five thousand, three hundred sixty-one".