121927681 has 4 divisors (see below), whose sum is σ = 125860864. Its totient is φ = 117994500.

The previous prime is 121927679. The next prime is 121927717. The reversal of 121927681 is 186729121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 186729121 = 37 ⋅5046733.

It is a cyclic number.

It is not a de Polignac number, because 121927681 - 2¹ = 121927679 is a prime.

It is a super-2 number, since 2×121927681² = 29732718788075522, which contains 22 as substring.

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 121927681.

It is not an unprimeable number, because it can be changed into a prime (121927651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1966545 + ... + 1966606.

It is an arithmetic number, because the mean of its divisors is an integer number (31465216).

Almost surely, 2^121927681 is an apocalyptic number.

It is an amenable number.

121927681 is a deficient number, since it is larger than the sum of its proper divisors (3933183).

121927681 is an equidigital number, since it uses as much as digits as its factorization.

121927681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3933182.

The product of its digits is 12096, while the sum is 37.

The square root of 121927681 is about 11042.0868045854. The cubic root of 121927681 is about 495.8695473460.

It can be divided in two parts, 1219 and 27681, that added together give a square (28900 = 170²).

The spelling of 121927681 in words is "one hundred twenty-one million, nine hundred twenty-seven thousand, six hundred eighty-one".