642897129 has 32 divisors (see below), whose sum is σ = 1033600000. Its totient is φ = 347229504.

The previous prime is 642897121. The next prime is 642897133. The reversal of 642897129 is 921798246.

642897129 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 642897129 - 2³ = 642897121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (642897121) 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, 197487 + ... + 200715.

It is an arithmetic number, because the mean of its divisors is an integer number (32300000).

Almost surely, 2^642897129 is an apocalyptic number.

It is an amenable number.

642897129 is a deficient number, since it is larger than the sum of its proper divisors (390702871).

642897129 is a wasteful number, since it uses less digits than its factorization.

642897129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3757.

The product of its digits is 435456, while the sum is 48.

The square root of 642897129 is about 25355.4161669652. The cubic root of 642897129 is about 863.0722678120.

The spelling of 642897129 in words is "six hundred forty-two million, eight hundred ninety-seven thousand, one hundred twenty-nine".