49857721 has 9 divisors (see below), whose sum is σ = 52290021. Its totient is φ = 47534652.

The previous prime is 49857713. The next prime is 49857733. The reversal of 49857721 is 12775894.

The square root of 49857721 is 7061.

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

It is not a de Polignac number, because 49857721 - 2³ = 49857713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (49857701) 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, 162250 + ... + 162556.

Almost surely, 2^49857721 is an apocalyptic number.

49857721 is the 7061-st square number.

49857721 is the 3531-st centered octagonal number.

It is an amenable number.

49857721 is a deficient number, since it is larger than the sum of its proper divisors (2432300).

49857721 is an frugal number, since it uses more digits than its factorization.

49857721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660 (or 330 counting only the distinct ones).

The product of its digits is 141120, while the sum is 43.

The cubic root of 49857721 is about 368.0533776740.

Subtracting from 49857721 its product of digits (141120), we obtain a square (49716601 = 7051²).

The spelling of 49857721 in words is "forty-nine million, eight hundred fifty-seven thousand, seven hundred twenty-one".