121637638 has 4 divisors (see below), whose sum is σ = 182456460. Its totient is φ = 60818818.

The previous prime is 121637627. The next prime is 121637647. The reversal of 121637638 is 836736121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 836736121 = 13 ⋅64364317.

It is a junction number, because it is equal to n+sod(n) for n = 121637597 and 121637606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30409408 + ... + 30409411.

It is an arithmetic number, because the mean of its divisors is an integer number (45614115).

Almost surely, 2^121637638 is an apocalyptic number.

121637638 is a deficient number, since it is larger than the sum of its proper divisors (60818822).

121637638 is an equidigital number, since it uses as much as digits as its factorization.

121637638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60818821.

The product of its digits is 36288, while the sum is 37.

The square root of 121637638 is about 11028.9454618291. The cubic root of 121637638 is about 495.4760417206.

The spelling of 121637638 in words is "one hundred twenty-one million, six hundred thirty-seven thousand, six hundred thirty-eight".