20645646342 has 16 divisors (see below), whose sum is σ = 41293070400. Its totient is φ = 6881585832.

The previous prime is 20645646323. The next prime is 20645646353. The reversal of 20645646342 is 24364654602.

It is a junction number, because it is equal to n+sod(n) for n = 20645646294 and 20645646303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113409 + ... + 232707.

It is an arithmetic number, because the mean of its divisors is an integer number (2580816900).

Almost surely, 2^20645646342 is an apocalyptic number.

20645646342 is an abundant number, since it is smaller than the sum of its proper divisors (20647424058).

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

20645646342 is a wasteful number, since it uses less digits than its factorization.

20645646342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148147.

The product of its (nonzero) digits is 829440, while the sum is 42.

The spelling of 20645646342 in words is "twenty billion, six hundred forty-five million, six hundred forty-six thousand, three hundred forty-two".