642621632122 has 16 divisors (see below), whose sum is σ = 974939146560. Its totient is φ = 317654250048.

The previous prime is 642621632087. The next prime is 642621632129. The reversal of 642621632122 is 221236126246.

It is a super-2 number, since 2×642621632122² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (642621632129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2978847 + ... + 3187282.

It is an arithmetic number, because the mean of its divisors is an integer number (60933696660).

Almost surely, 2^642621632122 is an apocalyptic number.

642621632122 is a deficient number, since it is larger than the sum of its proper divisors (332317514438).

642621632122 is a wasteful number, since it uses less digits than its factorization.

642621632122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6166725.

The product of its digits is 82944, while the sum is 37.

Adding to 642621632122 its reverse (221236126246), we get a palindrome (863857758368).

The spelling of 642621632122 in words is "six hundred forty-two billion, six hundred twenty-one million, six hundred thirty-two thousand, one hundred twenty-two".