42721567646 has 32 divisors (see below), whose sum is σ = 65853868320. Its totient is φ = 20778886656.

The previous prime is 42721567643. The next prime is 42721567657. The reversal of 42721567646 is 64676512724.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 42721567594 and 42721567603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42721567643) 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, 11888426 + ... + 11892018.

It is an arithmetic number, because the mean of its divisors is an integer number (2057933385).

Almost surely, 2^42721567646 is an apocalyptic number.

42721567646 is a deficient number, since it is larger than the sum of its proper divisors (23132300674).

42721567646 is a wasteful number, since it uses less digits than its factorization.

42721567646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4748.

The product of its digits is 3386880, while the sum is 50.

The spelling of 42721567646 in words is "forty-two billion, seven hundred twenty-one million, five hundred sixty-seven thousand, six hundred forty-six".