61026781 has 2 divisors, whose sum is σ = 61026782. Its totient is φ = 61026780.

The previous prime is 61026773. The next prime is 61026799. The reversal of 61026781 is 18762016.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52852900 + 8173881 = 7270^2 + 2859^2 .

It is a cyclic number.

It is not a de Polignac number, because 61026781 - 2³ = 61026773 is a prime.

It is a super-2 number, since 2×61026781² = 7448535998443922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61020781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30513390 + 30513391.

It is an arithmetic number, because the mean of its divisors is an integer number (30513391).

Almost surely, 2^61026781 is an apocalyptic number.

It is an amenable number.

61026781 is a deficient number, since it is larger than the sum of its proper divisors (1).

61026781 is an equidigital number, since it uses as much as digits as its factorization.

61026781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 61026781 is about 7811.9639656107. The cubic root of 61026781 is about 393.7073182592.

Adding to 61026781 its reverse (18762016), we get a palindrome (79788797).

The spelling of 61026781 in words is "sixty-one million, twenty-six thousand, seven hundred eighty-one".