20405340142 has 64 divisors (see below), whose sum is σ = 36303531264. Its totient is φ = 8496714240.

The previous prime is 20405340133. The next prime is 20405340173. The reversal of 20405340142 is 24104350402.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4935108 + ... + 4939240.

It is an arithmetic number, because the mean of its divisors is an integer number (567242676).

Almost surely, 2^20405340142 is an apocalyptic number.

20405340142 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20405340142 is a deficient number, since it is larger than the sum of its proper divisors (15898191122).

20405340142 is a wasteful number, since it uses less digits than its factorization.

20405340142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4513.

The product of its (nonzero) digits is 3840, while the sum is 25.

Adding to 20405340142 its reverse (24104350402), we get a palindrome (44509690544).

The spelling of 20405340142 in words is "twenty billion, four hundred five million, three hundred forty thousand, one hundred forty-two".