61972181 has 2 divisors, whose sum is σ = 61972182. Its totient is φ = 61972180.

The previous prime is 61972171. The next prime is 61972201. The reversal of 61972181 is 18127916.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61371556 + 600625 = 7834^2 + 775^2 .

It is a cyclic number.

It is not a de Polignac number, because 61972181 - 2¹⁰ = 61971157 is a prime.

It is a super-2 number, since 2×61972181² = 7681102435793522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61972171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30986090 + 30986091.

It is an arithmetic number, because the mean of its divisors is an integer number (30986091).

Almost surely, 2^61972181 is an apocalyptic number.

It is an amenable number.

61972181 is a deficient number, since it is larger than the sum of its proper divisors (1).

61972181 is an equidigital number, since it uses as much as digits as its factorization.

61972181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 35.

The square root of 61972181 is about 7872.2411675456. The cubic root of 61972181 is about 395.7299560979.

The spelling of 61972181 in words is "sixty-one million, nine hundred seventy-two thousand, one hundred eighty-one".