640152745 has 4 divisors (see below), whose sum is σ = 768183300. Its totient is φ = 512122192.

The previous prime is 640152743. The next prime is 640152787. The reversal of 640152745 is 547251046.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 153685609 + 486467136 = 12397^2 + 22056^2 .

It is a cyclic number.

It is not a de Polignac number, because 640152745 - 2¹ = 640152743 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 640152745.

It is not an unprimeable number, because it can be changed into a prime (640152743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64015270 + ... + 64015279.

It is an arithmetic number, because the mean of its divisors is an integer number (192045825).

Almost surely, 2^640152745 is an apocalyptic number.

It is an amenable number.

640152745 is a deficient number, since it is larger than the sum of its proper divisors (128030555).

640152745 is a wasteful number, since it uses less digits than its factorization.

640152745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128030554.

The product of its (nonzero) digits is 33600, while the sum is 34.

The square root of 640152745 is about 25301.2399893760. The cubic root of 640152745 is about 861.8424287108.

The spelling of 640152745 in words is "six hundred forty million, one hundred fifty-two thousand, seven hundred forty-five".