721412105 has 4 divisors (see below), whose sum is σ = 865694532. Its totient is φ = 577129680.

The previous prime is 721412101. The next prime is 721412141. The reversal of 721412105 is 501214127.

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 224880016 + 496532089 = 14996^2 + 22283^2 .

It is not a de Polignac number, because 721412105 - 2² = 721412101 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (721412101) 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, 72141206 + ... + 72141215.

It is an arithmetic number, because the mean of its divisors is an integer number (216423633).

Almost surely, 2^721412105 is an apocalyptic number.

It is an amenable number.

721412105 is a deficient number, since it is larger than the sum of its proper divisors (144282427).

721412105 is a wasteful number, since it uses less digits than its factorization.

721412105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144282426.

The product of its (nonzero) digits is 560, while the sum is 23.

The square root of 721412105 is about 26859.1158640786. The cubic root of 721412105 is about 896.8665124102.

The spelling of 721412105 in words is "seven hundred twenty-one million, four hundred twelve thousand, one hundred five".