721099783542 has 64 divisors (see below), whose sum is σ = 1559820810240. Its totient is φ = 221372030976.

The previous prime is 721099783541. The next prime is 721099783561. The reversal of 721099783542 is 245387990127.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721099783541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33436959 + ... + 33458517.

It is an arithmetic number, because the mean of its divisors is an integer number (24372200160).

Almost surely, 2^721099783542 is an apocalyptic number.

721099783542 is an abundant number, since it is smaller than the sum of its proper divisors (838721026698).

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

721099783542 is a wasteful number, since it uses less digits than its factorization.

721099783542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28605.

The product of its (nonzero) digits is 7620480, while the sum is 57.

The spelling of 721099783542 in words is "seven hundred twenty-one billion, ninety-nine million, seven hundred eighty-three thousand, five hundred forty-two".