61066981 has 2 divisors, whose sum is σ = 61066982. Its totient is φ = 61066980.

The previous prime is 61066919. The next prime is 61066991. The reversal of 61066981 is 18966016.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60202081 + 864900 = 7759^2 + 930^2 .

It is a cyclic number.

It is not a de Polignac number, because 61066981 - 2⁷ = 61066853 is a prime.

It is a super-2 number, since 2×61066981² = 7458352336908722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 61066981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61066991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30533490 + 30533491.

It is an arithmetic number, because the mean of its divisors is an integer number (30533491).

Almost surely, 2^61066981 is an apocalyptic number.

It is an amenable number.

61066981 is a deficient number, since it is larger than the sum of its proper divisors (1).

61066981 is an equidigital number, since it uses as much as digits as its factorization.

61066981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 61066981 is about 7814.5365185659. The cubic root of 61066981 is about 393.7937478561.

The spelling of 61066981 in words is "sixty-one million, sixty-six thousand, nine hundred eighty-one".