121906981 has 32 divisors (see below), whose sum is σ = 150151680. Its totient is φ = 96768000.

The previous prime is 121906951. The next prime is 121906991. The reversal of 121906981 is 189609121.

It is not a de Polignac number, because 121906981 - 2¹¹ = 121904933 is a prime.

It is a super-2 number, since 2×121906981² = 29722624033068722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121906981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121906901) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 807256 + ... + 807406.

It is an arithmetic number, because the mean of its divisors is an integer number (4692240).

Almost surely, 2^121906981 is an apocalyptic number.

It is an amenable number.

121906981 is a deficient number, since it is larger than the sum of its proper divisors (28244699).

121906981 is a wasteful number, since it uses less digits than its factorization.

121906981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325.

The product of its (nonzero) digits is 7776, while the sum is 37.

The square root of 121906981 is about 11041.1494419739. The cubic root of 121906981 is about 495.8414840424.

The spelling of 121906981 in words is "one hundred twenty-one million, nine hundred six thousand, nine hundred eighty-one".