61545555 has 32 divisors (see below), whose sum is σ = 111283200. Its totient is φ = 32263776.

The previous prime is 61545553. The next prime is 61545557. The reversal of 61545555 is 55554516.

61545555 is a `hidden beast` number, since 61 + 5 + 45 + 555 = 666.

It is an interprime number because it is at equal distance from previous prime (61545553) and next prime (61545557).

It is not a de Polignac number, because 61545555 - 2¹ = 61545553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61545553) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4102 + ... + 11828.

It is an arithmetic number, because the mean of its divisors is an integer number (3477600).

Almost surely, 2^61545555 is an apocalyptic number.

61545555 is a deficient number, since it is larger than the sum of its proper divisors (49737645).

61545555 is a wasteful number, since it uses less digits than its factorization.

61545555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7800 (or 7794 counting only the distinct ones).

The product of its digits is 75000, while the sum is 36.

The square root of 61545555 is about 7845.0975137343. The cubic root of 61545555 is about 394.8197757114.

The spelling of 61545555 in words is "sixty-one million, five hundred forty-five thousand, five hundred fifty-five".