61906813 has 2 divisors, whose sum is σ = 61906814. Its totient is φ = 61906812.

The previous prime is 61906771. The next prime is 61906837. The reversal of 61906813 is 31860916.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55621764 + 6285049 = 7458^2 + 2507^2 .

It is a cyclic number.

It is not a de Polignac number, because 61906813 - 2¹³ = 61898621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61906913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30953406 + 30953407.

It is an arithmetic number, because the mean of its divisors is an integer number (30953407).

Almost surely, 2^61906813 is an apocalyptic number.

It is an amenable number.

61906813 is a deficient number, since it is larger than the sum of its proper divisors (1).

61906813 is an equidigital number, since it uses as much as digits as its factorization.

61906813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 61906813 is about 7868.0882684423. The cubic root of 61906813 is about 395.5907690419.

The spelling of 61906813 in words is "sixty-one million, nine hundred six thousand, eight hundred thirteen".