20642243026 has 4 divisors (see below), whose sum is σ = 30963364542. Its totient is φ = 10321121512.

The previous prime is 20642243023. The next prime is 20642243029. The reversal of 20642243026 is 62034224602.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20642243023) and next prime (20642243029).

It can be written as a sum of positive squares in only one way, i.e., 20484765625 + 157477401 = 143125^2 + 12549^2 .

It is a super-2 number, since 2×20642243026² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20642243023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5160560755 + ... + 5160560758.

Almost surely, 2^20642243026 is an apocalyptic number.

20642243026 is a deficient number, since it is larger than the sum of its proper divisors (10321121516).

20642243026 is a wasteful number, since it uses less digits than its factorization.

20642243026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10321121515.

The product of its (nonzero) digits is 27648, while the sum is 31.

Adding to 20642243026 its reverse (62034224602), we get a palindrome (82676467628).

The spelling of 20642243026 in words is "twenty billion, six hundred forty-two million, two hundred forty-three thousand, twenty-six".