61557077 has 4 divisors (see below), whose sum is σ = 61608876. Its totient is φ = 61505280.

The previous prime is 61557061. The next prime is 61557091. The reversal of 61557077 is 77075516.

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 31460881 + 30096196 = 5609^2 + 5486^2 .

It is a cyclic number.

It is not a de Polignac number, because 61557077 - 2⁴ = 61557061 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61557077.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61557007) 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, 24074 + ... + 26507.

It is an arithmetic number, because the mean of its divisors is an integer number (15402219).

Almost surely, 2^61557077 is an apocalyptic number.

It is an amenable number.

61557077 is a deficient number, since it is larger than the sum of its proper divisors (51799).

61557077 is a wasteful number, since it uses less digits than its factorization.

61557077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51798.

The product of its (nonzero) digits is 51450, while the sum is 38.

The square root of 61557077 is about 7845.8318233314. The cubic root of 61557077 is about 394.8444123653.

The spelling of 61557077 in words is "sixty-one million, five hundred fifty-seven thousand, seventy-seven".