640054990 has 8 divisors (see below), whose sum is σ = 1152099000. Its totient is φ = 256021992.

The previous prime is 640054967. The next prime is 640054991. The reversal of 640054990 is 99450046.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640054991) 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, 32002740 + ... + 32002759.

It is an arithmetic number, because the mean of its divisors is an integer number (144012375).

Almost surely, 2^640054990 is an apocalyptic number.

640054990 is a deficient number, since it is larger than the sum of its proper divisors (512044010).

640054990 is a wasteful number, since it uses less digits than its factorization.

640054990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64005506.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 640054990 is about 25299.3080933056. The cubic root of 640054990 is about 861.7985570483.

The spelling of 640054990 in words is "six hundred forty million, fifty-four thousand, nine hundred ninety".