721900705 has 8 divisors (see below), whose sum is σ = 867333312. Its totient is φ = 576818928.

The previous prime is 721900693. The next prime is 721900709. The reversal of 721900705 is 507009127.

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

It is a cyclic number.

It is not a de Polignac number, because 721900705 - 2²³ = 713512097 is a prime.

It is a super-2 number, since 2×721900705² = 1042281255758994050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (721900709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83157 + ... + 91426.

It is an arithmetic number, because the mean of its divisors is an integer number (108416664).

Almost surely, 2^721900705 is an apocalyptic number.

It is an amenable number.

721900705 is a deficient number, since it is larger than the sum of its proper divisors (145432607).

721900705 is a wasteful number, since it uses less digits than its factorization.

721900705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175415.

The product of its (nonzero) digits is 4410, while the sum is 31.

The square root of 721900705 is about 26868.2099329300. The cubic root of 721900705 is about 897.0689441325.

The spelling of 721900705 in words is "seven hundred twenty-one million, nine hundred thousand, seven hundred five".