642402123 has 32 divisors (see below), whose sum is σ = 947890944. Its totient is φ = 383760000.

The previous prime is 642402109. The next prime is 642402133. The reversal of 642402123 is 321204246.

It is not a de Polignac number, because 642402123 - 2⁵ = 642402091 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 642402093 and 642402102.

It is not an unprimeable number, because it can be changed into a prime (642402133) 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, 782053 + ... + 782873.

It is an arithmetic number, because the mean of its divisors is an integer number (29621592).

Almost surely, 2^642402123 is an apocalyptic number.

642402123 is a deficient number, since it is larger than the sum of its proper divisors (305488821).

642402123 is a wasteful number, since it uses less digits than its factorization.

642402123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147.

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 642402123 is about 25345.6529408891. The cubic root of 642402123 is about 862.8507001470.

Adding to 642402123 its reverse (321204246), we get a palindrome (963606369).

The spelling of 642402123 in words is "six hundred forty-two million, four hundred two thousand, one hundred twenty-three".