63725821 has 4 divisors (see below), whose sum is σ = 63776032. Its totient is φ = 63675612.

The previous prime is 63725797. The next prime is 63725839. The reversal of 63725821 is 12852736.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 63725821 - 2⁷ = 63725693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63725021) 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, 23151 + ... + 25756.

It is an arithmetic number, because the mean of its divisors is an integer number (15944008).

Almost surely, 2^63725821 is an apocalyptic number.

It is an amenable number.

63725821 is a deficient number, since it is larger than the sum of its proper divisors (50211).

63725821 is a wasteful number, since it uses less digits than its factorization.

63725821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50210.

The product of its digits is 20160, while the sum is 34.

The square root of 63725821 is about 7982.8454200241. The cubic root of 63725821 is about 399.4279761116.

It can be divided in two parts, 63725 and 821, that added together give a palindrome (64546).

The spelling of 63725821 in words is "sixty-three million, seven hundred twenty-five thousand, eight hundred twenty-one".