61606421 has 2 divisors, whose sum is σ = 61606422.
Its totient is φ = 61606420.
The previous prime is 61606409. The next prime is 61606439. The reversal of 61606421 is 12460616.
It is a happy number.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 45292900 + 16313521 = 6730^2 + 4039^2
It is a cyclic number.
It is not a de Polignac number, because 61606421 - 214 = 61590037 is a prime.
It is a super-2 number, since 2×616064212 = 7590702216858482, which contains 22 as substring.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (61606471) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30803210 + 30803211.
It is an arithmetic number, because the mean of its divisors is an integer number (30803211).
Almost surely, 261606421 is an apocalyptic number.
It is an amenable number.
61606421 is a deficient number, since it is larger than the sum of its proper divisors (1).
61606421 is an equidigital number, since it uses as much as digits as its factorization.
61606421 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 1728, while the sum is 26.
The square root of 61606421 is about 7848.9757930573.
The cubic root of 61606421 is about 394.9498862877.
The spelling of 61606421 in words is "sixty-one million, six hundred six thousand, four hundred twenty-one".