20406354240 has 112 divisors (see below), whose sum is σ = 65702931840. Its totient is φ = 5365032960.

The previous prime is 20406354173. The next prime is 20406354247. The reversal of 20406354240 is 4245360402.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 20406354198 and 20406354207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20406354247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81535 + ... + 217854.

It is an arithmetic number, because the mean of its divisors is an integer number (586633320).

Almost surely, 2^20406354240 is an apocalyptic number.

20406354240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20406354240 is an abundant number, since it is smaller than the sum of its proper divisors (45296577600).

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

20406354240 is a wasteful number, since it uses less digits than its factorization.

20406354240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299480 (or 299470 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 30.

The spelling of 20406354240 in words is "twenty billion, four hundred six million, three hundred fifty-four thousand, two hundred forty".