61031621 has 4 divisors (see below), whose sum is σ = 69750432. Its totient is φ = 52312812.

The previous prime is 61031617. The next prime is 61031651. The reversal of 61031621 is 12613016.

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 61031621 - 2² = 61031617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 61031593 and 61031602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61031651) 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, 4359395 + ... + 4359408.

It is an arithmetic number, because the mean of its divisors is an integer number (17437608).

Almost surely, 2^61031621 is an apocalyptic number.

It is an amenable number.

61031621 is a deficient number, since it is larger than the sum of its proper divisors (8718811).

61031621 is an equidigital number, since it uses as much as digits as its factorization.

61031621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8718810.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 61031621 is about 7812.2737407236. The cubic root of 61031621 is about 393.7177262201.

Adding to 61031621 its reverse (12613016), we get a palindrome (73644637).

The spelling of 61031621 in words is "sixty-one million, thirty-one thousand, six hundred twenty-one".