72405018638 has 8 divisors (see below), whose sum is σ = 109661970288. Its totient is φ = 35851028544.

The previous prime is 72405018613. The next prime is 72405018667. The reversal of 72405018638 is 83681050427.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent 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, 175740131 + ... + 175740542.

It is an arithmetic number, because the mean of its divisors is an integer number (13707746286).

Almost surely, 2^72405018638 is an apocalyptic number.

72405018638 is a deficient number, since it is larger than the sum of its proper divisors (37256951650).

72405018638 is a wasteful number, since it uses less digits than its factorization.

72405018638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351480778.

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 72405018638 in words is "seventy-two billion, four hundred five million, eighteen thousand, six hundred thirty-eight".