720438557638 has 16 divisors (see below), whose sum is σ = 1102749575760. Its totient is φ = 352902420000.

The previous prime is 720438557621. The next prime is 720438557639. The reversal of 720438557638 is 836755834027.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720438557639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11732793 + ... + 11794036.

It is an arithmetic number, because the mean of its divisors is an integer number (68921848485).

Almost surely, 2^720438557638 is an apocalyptic number.

720438557638 is a deficient number, since it is larger than the sum of its proper divisors (382311018122).

720438557638 is a wasteful number, since it uses less digits than its factorization.

720438557638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23527143.

The product of its (nonzero) digits is 33868800, while the sum is 58.

The spelling of 720438557638 in words is "seven hundred twenty billion, four hundred thirty-eight million, five hundred fifty-seven thousand, six hundred thirty-eight".