61501818 has 32 divisors (see below), whose sum is σ = 148846464. Its totient is φ = 16538112.

The previous prime is 61501789. The next prime is 61501819. The reversal of 61501818 is 81810516.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61501819) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42355 + ... + 43782.

It is an arithmetic number, because the mean of its divisors is an integer number (4651452).

Almost surely, 2^61501818 is an apocalyptic number.

61501818 is an abundant number, since it is smaller than the sum of its proper divisors (87344646).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61501818 is a wasteful number, since it uses less digits than its factorization.

61501818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86166.

The product of its (nonzero) digits is 1920, while the sum is 30.

The square root of 61501818 is about 7842.3094812689. The cubic root of 61501818 is about 394.7262280692.

The spelling of 61501818 in words is "sixty-one million, five hundred one thousand, eight hundred eighteen".