121971637 has 2 divisors, whose sum is σ = 121971638. Its totient is φ = 121971636.

The previous prime is 121971631. The next prime is 121971643. The reversal of 121971637 is 736179121.

It is a balanced prime because it is at equal distance from previous prime (121971631) and next prime (121971643).

It can be written as a sum of positive squares in only one way, i.e., 103917636 + 18054001 = 10194^2 + 4249^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121971637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121971596 and 121971605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121971631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60985818 + 60985819.

It is an arithmetic number, because the mean of its divisors is an integer number (60985819).

Almost surely, 2^121971637 is an apocalyptic number.

It is an amenable number.

121971637 is a deficient number, since it is larger than the sum of its proper divisors (1).

121971637 is an equidigital number, since it uses as much as digits as its factorization.

121971637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15876, while the sum is 37.

The square root of 121971637 is about 11044.0770098728. The cubic root of 121971637 is about 495.9291286292.

The spelling of 121971637 in words is "one hundred twenty-one million, nine hundred seventy-one thousand, six hundred thirty-seven".