20484899639 has 2 divisors, whose sum is σ = 20484899640. Its totient is φ = 20484899638.

The previous prime is 20484899629. The next prime is 20484899693. The reversal of 20484899639 is 93699848402.

Together with next prime (20484899693) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20484899639 - 2²⁸ = 20216464183 is a prime.

It is a super-2 number, since 2×20484899639² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20484899629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10242449819 + 10242449820.

It is an arithmetic number, because the mean of its divisors is an integer number (10242449820).

Almost surely, 2^20484899639 is an apocalyptic number.

20484899639 is a deficient number, since it is larger than the sum of its proper divisors (1).

20484899639 is an equidigital number, since it uses as much as digits as its factorization.

20484899639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26873856, while the sum is 62.

The spelling of 20484899639 in words is "twenty billion, four hundred eighty-four million, eight hundred ninety-nine thousand, six hundred thirty-nine".