103815721 has 9 divisors (see below), whose sum is σ = 108771229. Its totient is φ = 99077836.

The previous prime is 103815707. The next prime is 103815773. The reversal of 103815721 is 127518301.

The square root of 103815721 is 10189.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 103815721 - 2¹¹ = 103813673 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 103815721.

It is not an unprimeable number, because it can be changed into a prime (103815781) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 234126 + ... + 234568.

Almost surely, 2^103815721 is an apocalyptic number.

103815721 is the 10189-th square number.

103815721 is the 5095-th centered octagonal number.

It is an amenable number.

103815721 is a deficient number, since it is larger than the sum of its proper divisors (4955508).

103815721 is an frugal number, since it uses more digits than its factorization.

103815721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 932 (or 466 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 28.

The cubic root of 103815721 is about 469.9890158894.

The spelling of 103815721 in words is "one hundred three million, eight hundred fifteen thousand, seven hundred twenty-one".