642401401 has 2 divisors, whose sum is σ = 642401402. Its totient is φ = 642401400.

The previous prime is 642401371. The next prime is 642401411. The reversal of 642401401 is 104104246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 606341376 + 36060025 = 24624^2 + 6005^2 .

It is a cyclic number.

It is not a de Polignac number, because 642401401 - 2⁵ = 642401369 is a prime.

It is not a weakly prime, because it can be changed into another prime (642401411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321200700 + 321200701.

It is an arithmetic number, because the mean of its divisors is an integer number (321200701).

Almost surely, 2^642401401 is an apocalyptic number.

It is an amenable number.

642401401 is a deficient number, since it is larger than the sum of its proper divisors (1).

642401401 is an equidigital number, since it uses as much as digits as its factorization.

642401401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 642401401 is about 25345.6386978115. The cubic root of 642401401 is about 862.8503768923.

Adding to 642401401 its reverse (104104246), we get a palindrome (746505647).

The spelling of 642401401 in words is "six hundred forty-two million, four hundred one thousand, four hundred one".