121205757 has 16 divisors (see below), whose sum is σ = 163829952. Its totient is φ = 79699200.

The previous prime is 121205741. The next prime is 121205783. The reversal of 121205757 is 757502121.

It is not a de Polignac number, because 121205757 - 2⁴ = 121205741 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121205797) 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 15 ways as a sum of consecutive naturals, for example, 101518 + ... + 102704.

It is an arithmetic number, because the mean of its divisors is an integer number (10239372).

Almost surely, 2^121205757 is an apocalyptic number.

It is an amenable number.

121205757 is a deficient number, since it is larger than the sum of its proper divisors (42624195).

121205757 is a wasteful number, since it uses less digits than its factorization.

121205757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1628.

The product of its (nonzero) digits is 4900, while the sum is 30.

The square root of 121205757 is about 11009.3486183334. The cubic root of 121205757 is about 494.8889415167. Note that the first 3 decimals are identical.

Adding to 121205757 its reverse (757502121), we get a palindrome (878707878).

The spelling of 121205757 in words is "one hundred twenty-one million, two hundred five thousand, seven hundred fifty-seven".