61309471 has 2 divisors, whose sum is σ = 61309472. Its totient is φ = 61309470.

The previous prime is 61309433. The next prime is 61309487. The reversal of 61309471 is 17490316.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61309471 - 2⁷ = 61309343 is a prime.

It is a super-3 number, since 3×61309471³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61309571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30654735 + 30654736.

It is an arithmetic number, because the mean of its divisors is an integer number (30654736).

Almost surely, 2^61309471 is an apocalyptic number.

61309471 is a deficient number, since it is larger than the sum of its proper divisors (1).

61309471 is an equidigital number, since it uses as much as digits as its factorization.

61309471 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 61309471 is about 7830.0364622395. The cubic root of 61309471 is about 394.3142961010.

Adding to 61309471 its reverse (17490316), we get a palindrome (78799787).

The spelling of 61309471 in words is "sixty-one million, three hundred nine thousand, four hundred seventy-one".