20400231432 has 128 divisors (see below), whose sum is σ = 60880527360. Its totient is φ = 5569724160.

The previous prime is 20400231329. The next prime is 20400231437. The reversal of 20400231432 is 23413200402.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 20400231399 and 20400231408.

It is not an unprimeable number, because it can be changed into a prime (20400231437) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5334273 + ... + 5338095.

It is an arithmetic number, because the mean of its divisors is an integer number (475629120).

Almost surely, 2^20400231432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20400231432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30440263680).

20400231432 is an abundant number, since it is smaller than the sum of its proper divisors (40480295928).

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

20400231432 is a wasteful number, since it uses less digits than its factorization.

20400231432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5243 (or 5239 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

Adding to 20400231432 its reverse (23413200402), we get a palindrome (43813431834).

The spelling of 20400231432 in words is "twenty billion, four hundred million, two hundred thirty-one thousand, four hundred thirty-two".