121721371 has 2 divisors, whose sum is σ = 121721372. Its totient is φ = 121721370.

The previous prime is 121721363. The next prime is 121721393. The reversal of 121721371 is 173127121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121721371 - 2³ = 121721363 is a prime.

It is not a weakly prime, because it can be changed into another prime (121721351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60860685 + 60860686.

It is an arithmetic number, because the mean of its divisors is an integer number (60860686).

Almost surely, 2^121721371 is an apocalyptic number.

121721371 is a deficient number, since it is larger than the sum of its proper divisors (1).

121721371 is an equidigital number, since it uses as much as digits as its factorization.

121721371 is an evil number, because the sum of its binary digits is even.

The product of its digits is 588, while the sum is 25.

The square root of 121721371 is about 11032.7408652610. The cubic root of 121721371 is about 495.5897076877.

Adding to 121721371 its reverse (173127121), we get a palindrome (294848492).

The spelling of 121721371 in words is "one hundred twenty-one million, seven hundred twenty-one thousand, three hundred seventy-one".