121253561 has 16 divisors (see below), whose sum is σ = 145490688. Its totient is φ = 99580800.

The previous prime is 121253533. The next prime is 121253567. The reversal of 121253561 is 165352121.

It is a de Polignac number, because none of the positive numbers 2^k-121253561 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 121253561.

It is not an unprimeable number, because it can be changed into a prime (121253567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2300 + ... + 15741.

It is an arithmetic number, because the mean of its divisors is an integer number (9093168).

Almost surely, 2^121253561 is an apocalyptic number.

121253561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121253561 is a deficient number, since it is larger than the sum of its proper divisors (24237127).

121253561 is a wasteful number, since it uses less digits than its factorization.

121253561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18112.

The product of its digits is 1800, while the sum is 26.

The square root of 121253561 is about 11011.5194682659. The cubic root of 121253561 is about 494.9539949762.

The spelling of 121253561 in words is "one hundred twenty-one million, two hundred fifty-three thousand, five hundred sixty-one".