121307981 has 8 divisors (see below), whose sum is σ = 122143224. Its totient is φ = 120476160.

The previous prime is 121307959. The next prime is 121307983. The reversal of 121307981 is 189703121.

It can be written as a sum of positive squares in 4 ways, for example, as 24108100 + 97199881 = 4910^2 + 9859^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121307981 is a prime.

It is a super-2 number, since 2×121307981² = 29431252508592722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121307983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 121175 + ... + 122171.

It is an arithmetic number, because the mean of its divisors is an integer number (15267903).

Almost surely, 2^121307981 is an apocalyptic number.

It is an amenable number.

121307981 is a deficient number, since it is larger than the sum of its proper divisors (835243).

121307981 is an equidigital number, since it uses as much as digits as its factorization.

121307981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1711.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 121307981 is about 11013.9902396906. The cubic root of 121307981 is about 495.0280309263.

The spelling of 121307981 in words is "one hundred twenty-one million, three hundred seven thousand, nine hundred eighty-one".