61052550781 has 4 divisors (see below), whose sum is σ = 61070558464.
Its totient is φ = 61034543100.
The previous prime is 61052550763. The next prime is 61052550799. The reversal of 61052550781 is 18705525016.
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 an interprime number because it is at equal distance from previous prime (61052550763) and next prime (61052550799).
It is a cyclic number.
It is not a de Polignac number, because 61052550781 - 219 = 61052026493 is a prime.
It is a super-2 number, since 2×610525507812 (a number of 22 digits) contains 22 as substring.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (61052550731) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (23) of ones.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8998755 + ... + 9005536.
It is an arithmetic number, because the mean of its divisors is an integer number (15267639616).
Almost surely, 261052550781 is an apocalyptic number.
It is an amenable number.
61052550781 is a deficient number, since it is larger than the sum of its proper divisors (18007683).
61052550781 is a wasteful number, since it uses less digits than its factorization.
61052550781 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 18007682.
The product of its (nonzero) digits is 84000, while the sum is 40.
The spelling of 61052550781 in words is "sixty-one billion, fifty-two million, five hundred fifty thousand, seven hundred eighty-one".