61263752181 has 4 divisors (see below), whose sum is σ = 81685002912. Its totient is φ = 40842501452.

The previous prime is 61263752167. The next prime is 61263752203. The reversal of 61263752181 is 18125736216.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61263752181 - 2²³ = 61255363573 is a prime.

It is a super-2 number, since 2×61263752181² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61263752141) 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, 10210625361 + ... + 10210625366.

It is an arithmetic number, because the mean of its divisors is an integer number (20421250728).

Almost surely, 2^61263752181 is an apocalyptic number.

It is an amenable number.

61263752181 is a deficient number, since it is larger than the sum of its proper divisors (20421250731).

61263752181 is a wasteful number, since it uses less digits than its factorization.

61263752181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20421250730.

The product of its digits is 120960, while the sum is 42.

The spelling of 61263752181 in words is "sixty-one billion, two hundred sixty-three million, seven hundred fifty-two thousand, one hundred eighty-one".