121657541 has 2 divisors, whose sum is σ = 121657542. Its totient is φ = 121657540.

The previous prime is 121657483. The next prime is 121657553. The reversal of 121657541 is 145756121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118156900 + 3500641 = 10870^2 + 1871^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121657541 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121657498 and 121657507.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121657841) 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, 60828770 + 60828771.

It is an arithmetic number, because the mean of its divisors is an integer number (60828771).

Almost surely, 2^121657541 is an apocalyptic number.

It is an amenable number.

121657541 is a deficient number, since it is larger than the sum of its proper divisors (1).

121657541 is an equidigital number, since it uses as much as digits as its factorization.

121657541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8400, while the sum is 32.

The square root of 121657541 is about 11029.8477324032. The cubic root of 121657541 is about 495.5030643922.

The spelling of 121657541 in words is "one hundred twenty-one million, six hundred fifty-seven thousand, five hundred forty-one".