61313621 has 4 divisors (see below), whose sum is σ = 61353612. Its totient is φ = 61273632.

The previous prime is 61313617. The next prime is 61313647. The reversal of 61313621 is 12631316.

It is a happy number.

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 15602500 + 45711121 = 3950^2 + 6761^2 .

It is a cyclic number.

It is not a de Polignac number, because 61313621 - 2² = 61313617 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 (61313671) 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, 17600 + ... + 20793.

It is an arithmetic number, because the mean of its divisors is an integer number (15338403).

Almost surely, 2^61313621 is an apocalyptic number.

It is an amenable number.

61313621 is a deficient number, since it is larger than the sum of its proper divisors (39991).

61313621 is a wasteful number, since it uses less digits than its factorization.

61313621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39990.

The product of its digits is 648, while the sum is 23.

The square root of 61313621 is about 7830.3014629068. The cubic root of 61313621 is about 394.3231928635.

Adding to 61313621 its reverse (12631316), we get a palindrome (73944937).

The spelling of 61313621 in words is "sixty-one million, three hundred thirteen thousand, six hundred twenty-one".