20400422016 has 128 divisors (see below), whose sum is σ = 58750776000. Its totient is φ = 6234697728.

The previous prime is 20400421963. The next prime is 20400422023. The reversal of 20400422016 is 61022400402.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 20400421983 and 20400422001.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 730095 + ... + 757521.

Almost surely, 2^20400422016 is an apocalyptic number.

20400422016 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20400422016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29375388000).

20400422016 is an abundant number, since it is smaller than the sum of its proper divisors (38350353984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20400422016 is a wasteful number, since it uses less digits than its factorization.

20400422016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27606 (or 27594 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 20400422016 its reverse (61022400402), we get a palindrome (81422822418).

The spelling of 20400422016 in words is "twenty billion, four hundred million, four hundred twenty-two thousand, sixteen".