20405318643724 has 12 divisors (see below), whose sum is σ = 40810637287504. Its totient is φ = 8745136561584.

The previous prime is 20405318643709. The next prime is 20405318643767. The reversal of 20405318643724 is 42734681350402.

20405318643724 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364380690039 + ... + 364380690094.

Almost surely, 2^{20405318643724} is an apocalyptic number.

It is an amenable number.

20405318643724 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20405318643724 is a wasteful number, since it uses less digits than its factorization.

20405318643724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728761380144 (or 728761380142 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 49.

The spelling of 20405318643724 in words is "twenty trillion, four hundred five billion, three hundred eighteen million, six hundred forty-three thousand, seven hundred twenty-four".