20420399999 has 8 divisors (see below), whose sum is σ = 20535939840. Its totient is φ = 20304950400.

The previous prime is 20420399953. The next prime is 20420400023. The reversal of 20420399999 is 99999302402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20420399999 - 2⁸ = 20420399743 is a prime.

It is a super-2 number, since 2×20420399999² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20420399599) 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, 460307 + ... + 502715.

It is an arithmetic number, because the mean of its divisors is an integer number (2566992480).

Almost surely, 2^20420399999 is an apocalyptic number.

20420399999 is a deficient number, since it is larger than the sum of its proper divisors (115539841).

20420399999 is a wasteful number, since it uses less digits than its factorization.

20420399999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45121.

The product of its (nonzero) digits is 2834352, while the sum is 56.

The spelling of 20420399999 in words is "twenty billion, four hundred twenty million, three hundred ninety-nine thousand, nine hundred ninety-nine".