661012441 has 4 divisors (see below), whose sum is σ = 661139584.
Its totient is φ = 660885300.
The previous prime is 661012427. The next prime is 661012463. The reversal of 661012441 is 144210166.
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 144210166 = 2 ⋅72105083.
It is a cyclic number.
It is not a de Polignac number, because 661012441 - 29 = 661011929 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (661015441) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (19) of ones.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55425 + ... + 66286.
It is an arithmetic number, because the mean of its divisors is an integer number (165284896).
Almost surely, 2661012441 is an apocalyptic number.
It is an amenable number.
661012441 is a deficient number, since it is larger than the sum of its proper divisors (127143).
661012441 is a wasteful number, since it uses less digits than its factorization.
661012441 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 127142.
The product of its (nonzero) digits is 1152, while the sum is 25.
The square root of 661012441 is about 25710.1622126349.
The cubic root of 661012441 is about 871.1037389571.
The spelling of 661012441 in words is "six hundred sixty-one million, twelve thousand, four hundred forty-one".