61820618 has 4 divisors (see below), whose sum is σ = 92730930. Its totient is φ = 30910308.

The previous prime is 61820609. The next prime is 61820621. The reversal of 61820618 is 81602816.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 39476089 + 22344529 = 6283^2 + 4727^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15455153 + ... + 15455156.

Almost surely, 2^61820618 is an apocalyptic number.

61820618 is a deficient number, since it is larger than the sum of its proper divisors (30910312).

61820618 is a wasteful number, since it uses less digits than its factorization.

61820618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30910311.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 61820618 is about 7862.6088545724. The cubic root of 61820618 is about 395.4070855226.

The spelling of 61820618 in words is "sixty-one million, eight hundred twenty thousand, six hundred eighteen".