61662109 has 2 divisors, whose sum is σ = 61662110. Its totient is φ = 61662108.

The previous prime is 61662089. The next prime is 61662113. The reversal of 61662109 is 90126616.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43599609 + 18062500 = 6603^2 + 4250^2 .

It is a cyclic number.

It is not a de Polignac number, because 61662109 - 2⁷ = 61661981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61662119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30831054 + 30831055.

It is an arithmetic number, because the mean of its divisors is an integer number (30831055).

Almost surely, 2^61662109 is an apocalyptic number.

It is an amenable number.

61662109 is a deficient number, since it is larger than the sum of its proper divisors (1).

61662109 is an equidigital number, since it uses as much as digits as its factorization.

61662109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 61662109 is about 7852.5224609676. The cubic root of 61662109 is about 395.0688530297.

The spelling of 61662109 in words is "sixty-one million, six hundred sixty-two thousand, one hundred nine".