61218203 has 4 divisors (see below), whose sum is σ = 63879888. Its totient is φ = 58556520.

The previous prime is 61218193. The next prime is 61218251. The reversal of 61218203 is 30281216.

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

It is a cyclic number.

It is not a de Polignac number, because 61218203 - 2¹⁶ = 61152667 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 2661661 = 61218203 / (6 + 1 + 2 + 1 + 8 + 2 + 0 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61218253) 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, 1330808 + ... + 1330853.

It is an arithmetic number, because the mean of its divisors is an integer number (15969972).

Almost surely, 2^61218203 is an apocalyptic number.

61218203 is a deficient number, since it is larger than the sum of its proper divisors (2661685).

61218203 is a wasteful number, since it uses less digits than its factorization.

61218203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2661684.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 61218203 is about 7824.2062217199. The cubic root of 61218203 is about 394.1185343408.

Adding to 61218203 its reverse (30281216), we get a palindrome (91499419).

The spelling of 61218203 in words is "sixty-one million, two hundred eighteen thousand, two hundred three".