121637 has 2 divisors, whose sum is σ = 121638. Its totient is φ = 121636.

The previous prime is 121633. The next prime is 121661. The reversal of 121637 is 736121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64516 + 57121 = 254^2 + 239^2 .

It is an emirp because it is prime and its reverse (736121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121637 - 2² = 121633 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60818 + 60819.

It is an arithmetic number, because the mean of its divisors is an integer number (60819).

2¹²¹⁶³⁷ is an apocalyptic number.

It is an amenable number.

121637 is a deficient number, since it is larger than the sum of its proper divisors (1).

121637 is an equidigital number, since it uses as much as digits as its factorization.

121637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 252, while the sum is 20.

The square root of 121637 is about 348.7649638367. The cubic root of 121637 is about 49.5475175447.

Adding to 121637 its reverse (736121), we get a palindrome (857758).

It can be divided in two parts, 121 and 637, that multiplied together give a palindrome (77077).

The spelling of 121637 in words is "one hundred twenty-one thousand, six hundred thirty-seven".