121751605 has 8 divisors (see below), whose sum is σ = 146191032. Its totient is φ = 97341888.

The previous prime is 121751593. The next prime is 121751611. The reversal of 121751605 is 506157121.

It can be written as a sum of positive squares in 4 ways, for example, as 68644 + 121682961 = 262^2 + 11031^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121751605 - 2²¹ = 119654453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2899 + ... + 15871.

It is an arithmetic number, because the mean of its divisors is an integer number (18273879).

Almost surely, 2^121751605 is an apocalyptic number.

It is an amenable number.

121751605 is a deficient number, since it is larger than the sum of its proper divisors (24439427).

121751605 is a wasteful number, since it uses less digits than its factorization.

121751605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14855.

The product of its (nonzero) digits is 2100, while the sum is 28.

The square root of 121751605 is about 11034.1109746096. The cubic root of 121751605 is about 495.6307369627.

The spelling of 121751605 in words is "one hundred twenty-one million, seven hundred fifty-one thousand, six hundred five".