63781121 has 8 divisors (see below), whose sum is σ = 66367080. Its totient is φ = 61220992.

The previous prime is 63781111. The next prime is 63781129. The reversal of 63781121 is 12118736.

It can be written as a sum of positive squares in 4 ways, for example, as 40500496 + 23280625 = 6364^2 + 4825^2 .

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 63781121 - 2⁶ = 63781057 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is not an unprimeable number, because it can be changed into a prime (63781129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1340 + ... + 11373.

It is an arithmetic number, because the mean of its divisors is an integer number (8295885).

Almost surely, 2^63781121 is an apocalyptic number.

It is an amenable number.

63781121 is a deficient number, since it is larger than the sum of its proper divisors (2585959).

63781121 is a wasteful number, since it uses less digits than its factorization.

63781121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12915.

The product of its digits is 2016, while the sum is 29.

The square root of 63781121 is about 7986.3083461635. The cubic root of 63781121 is about 399.5434812581.

Adding to 63781121 its reverse (12118736), we get a palindrome (75899857).

The spelling of 63781121 in words is "sixty-three million, seven hundred eighty-one thousand, one hundred twenty-one".