721543101626440 has 16 divisors (see below), whose sum is σ = 1623471978659580. Its totient is φ = 288617240650560.

The previous prime is 721543101626429. The next prime is 721543101626467. The reversal of 721543101626440 is 44626101345127.

It can be written as a sum of positive squares in 2 ways, for example, as 712495001530404 + 9048100096036 = 26692602^2 + 3008006^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9019288770291 + ... + 9019288770370.

Almost surely, 2^{721543101626440} is an apocalyptic number.

It is an amenable number.

721543101626440 is an abundant number, since it is smaller than the sum of its proper divisors (901928877033140).

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

721543101626440 is a wasteful number, since it uses less digits than its factorization.

721543101626440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18038577540672 (or 18038577540668 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 46.

The spelling of 721543101626440 in words is "seven hundred twenty-one trillion, five hundred forty-three billion, one hundred one million, six hundred twenty-six thousand, four hundred forty".