61320557 has 4 divisors (see below), whose sum is σ = 61354716. Its totient is φ = 61286400.

The previous prime is 61320551. The next prime is 61320601. The reversal of 61320557 is 75502316.

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 9897316 + 51423241 = 3146^2 + 7171^2 .

It is a cyclic number.

It is not a de Polignac number, because 61320557 - 2⁴ = 61320541 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 (61320551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14228 + ... + 18029.

It is an arithmetic number, because the mean of its divisors is an integer number (15338679).

Almost surely, 2^61320557 is an apocalyptic number.

It is an amenable number.

61320557 is a deficient number, since it is larger than the sum of its proper divisors (34159).

61320557 is a wasteful number, since it uses less digits than its factorization.

61320557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34158.

The product of its (nonzero) digits is 6300, while the sum is 29.

The square root of 61320557 is about 7830.7443452075. The cubic root of 61320557 is about 394.3380613516.

The spelling of 61320557 in words is "sixty-one million, three hundred twenty thousand, five hundred fifty-seven".