640014261 has 8 divisors (see below), whose sum is σ = 890454720. Its totient is φ = 408124992.

The previous prime is 640014239. The next prime is 640014281. The reversal of 640014261 is 162410046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640014261 - 2¹¹ = 640012213 is a prime.

It is a super-2 number, since 2×640014261² = 819236508566752242, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640014211) 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 7 ways as a sum of consecutive naturals, for example, 4637716 + ... + 4637853.

It is an arithmetic number, because the mean of its divisors is an integer number (111306840).

Almost surely, 2^640014261 is an apocalyptic number.

It is an amenable number.

640014261 is a deficient number, since it is larger than the sum of its proper divisors (250440459).

640014261 is a wasteful number, since it uses less digits than its factorization.

640014261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9275595.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 640014261 is about 25298.5031375376. The cubic root of 640014261 is about 861.7802768804.

The spelling of 640014261 in words is "six hundred forty million, fourteen thousand, two hundred sixty-one".