61564549 has 2 divisors, whose sum is σ = 61564550. Its totient is φ = 61564548.

The previous prime is 61564511. The next prime is 61564561. The reversal of 61564549 is 94546516.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41152225 + 20412324 = 6415^2 + 4518^2 .

It is a cyclic number.

It is not a de Polignac number, because 61564549 - 2⁷ = 61564421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61564849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30782274 + 30782275.

It is an arithmetic number, because the mean of its divisors is an integer number (30782275).

Almost surely, 2^61564549 is an apocalyptic number.

It is an amenable number.

61564549 is a deficient number, since it is larger than the sum of its proper divisors (1).

61564549 is an equidigital number, since it uses as much as digits as its factorization.

61564549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 40.

The square root of 61564549 is about 7846.3079852884. The cubic root of 61564549 is about 394.8603875557.

The spelling of 61564549 in words is "sixty-one million, five hundred sixty-four thousand, five hundred forty-nine".