639654105 has 32 divisors (see below), whose sum is σ = 1055157120. Its totient is φ = 330739200.

The previous prime is 639654097. The next prime is 639654107. The reversal of 639654105 is 501456936.

It is not a de Polignac number, because 639654105 - 2³ = 639654097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (639654107) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59655 + ... + 69555.

It is an arithmetic number, because the mean of its divisors is an integer number (32973660).

Almost surely, 2^639654105 is an apocalyptic number.

It is an amenable number.

639654105 is a deficient number, since it is larger than the sum of its proper divisors (415503015).

639654105 is a wasteful number, since it uses less digits than its factorization.

639654105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10041.

The product of its (nonzero) digits is 97200, while the sum is 39.

The square root of 639654105 is about 25291.3840072069. The cubic root of 639654105 is about 861.6185963295.

The spelling of 639654105 in words is "six hundred thirty-nine million, six hundred fifty-four thousand, one hundred five".