721650237145 has 4 divisors (see below), whose sum is σ = 865980284580. Its totient is φ = 577320189712.

The previous prime is 721650237127. The next prime is 721650237149. The reversal of 721650237145 is 541732056127.

It is a happy number.

721650237145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 168868396096 + 552781841049 = 410936^2 + 743493^2 .

It is a cyclic number.

It is not a de Polignac number, because 721650237145 - 2⁷ = 721650237017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (721650237149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72165023710 + ... + 72165023719.

It is an arithmetic number, because the mean of its divisors is an integer number (216495071145).

Almost surely, 2^721650237145 is an apocalyptic number.

It is an amenable number.

721650237145 is a deficient number, since it is larger than the sum of its proper divisors (144330047435).

721650237145 is a wasteful number, since it uses less digits than its factorization.

721650237145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144330047434.

The product of its (nonzero) digits is 352800, while the sum is 43.

The spelling of 721650237145 in words is "seven hundred twenty-one billion, six hundred fifty million, two hundred thirty-seven thousand, one hundred forty-five".