61166722281 has 32 divisors (see below), whose sum is σ = 95820177408. Its totient is φ = 33982113600.

The previous prime is 61166722277. The next prime is 61166722283. The reversal of 61166722281 is 18222766116.

It is a happy number.

It is not a de Polignac number, because 61166722281 - 2² = 61166722277 is a prime.

It is a super-2 number, since 2×61166722281² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61166722283) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56170 + ... + 354243.

It is an arithmetic number, because the mean of its divisors is an integer number (2994380544).

Almost surely, 2^61166722281 is an apocalyptic number.

It is an amenable number.

61166722281 is a deficient number, since it is larger than the sum of its proper divisors (34653455127).

61166722281 is a wasteful number, since it uses less digits than its factorization.

61166722281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410621.

The product of its digits is 96768, while the sum is 42.

The spelling of 61166722281 in words is "sixty-one billion, one hundred sixty-six million, seven hundred twenty-two thousand, two hundred eighty-one".