121767661 has 4 divisors (see below), whose sum is σ = 121792000. Its totient is φ = 121743324.

The previous prime is 121767649. The next prime is 121767691. The reversal of 121767661 is 166767121.

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: 166767121 = 5087 ⋅32783.

It is a cyclic number.

It is not a de Polignac number, because 121767661 - 2¹⁷ = 121636589 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121767661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121767631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1611 + ... + 15688.

It is an arithmetic number, because the mean of its divisors is an integer number (30448000).

Almost surely, 2^121767661 is an apocalyptic number.

It is an amenable number.

121767661 is a deficient number, since it is larger than the sum of its proper divisors (24339).

121767661 is an equidigital number, since it uses as much as digits as its factorization.

121767661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24338.

The product of its digits is 21168, while the sum is 37.

The square root of 121767661 is about 11034.8385126381. The cubic root of 121767661 is about 495.6525231158.

The spelling of 121767661 in words is "one hundred twenty-one million, seven hundred sixty-seven thousand, six hundred sixty-one".