61641421 has 2 divisors, whose sum is σ = 61641422. Its totient is φ = 61641420.

The previous prime is 61641413. The next prime is 61641431. The reversal of 61641421 is 12414616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53085796 + 8555625 = 7286^2 + 2925^2 .

It is a cyclic number.

It is not a de Polignac number, because 61641421 - 2³ = 61641413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61641431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30820710 + 30820711.

It is an arithmetic number, because the mean of its divisors is an integer number (30820711).

Almost surely, 2^61641421 is an apocalyptic number.

It is an amenable number.

61641421 is a deficient number, since it is larger than the sum of its proper divisors (1).

61641421 is an equidigital number, since it uses as much as digits as its factorization.

61641421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 25.

The square root of 61641421 is about 7851.2050667398. The cubic root of 61641421 is about 395.0246654469.

The spelling of 61641421 in words is "sixty-one million, six hundred forty-one thousand, four hundred twenty-one".