121615541 has 2 divisors, whose sum is σ = 121615542. Its totient is φ = 121615540.

The previous prime is 121615537. The next prime is 121615583. The reversal of 121615541 is 145516121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 120340900 + 1274641 = 10970^2 + 1129^2 .

It is an emirp because it is prime and its reverse (145516121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121615541 - 2² = 121615537 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 121615541.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121665541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60807770 + 60807771.

It is an arithmetic number, because the mean of its divisors is an integer number (60807771).

Almost surely, 2^121615541 is an apocalyptic number.

It is an amenable number.

121615541 is a deficient number, since it is larger than the sum of its proper divisors (1).

121615541 is an equidigital number, since it uses as much as digits as its factorization.

121615541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1200, while the sum is 26.

The square root of 121615541 is about 11027.9436433090. The cubic root of 121615541 is about 495.4460367613.

The spelling of 121615541 in words is "one hundred twenty-one million, six hundred fifteen thousand, five hundred forty-one".