121697999 has 4 divisors (see below), whose sum is σ = 123238560. Its totient is φ = 120157440.

The previous prime is 121697987. The next prime is 121698001. The reversal of 121697999 is 999796121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999796121 = 1787 ⋅559483.

It is a cyclic number.

It is not a de Polignac number, because 121697999 - 2¹² = 121693903 is a prime.

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 121697999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121697959) 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, 770162 + ... + 770319.

It is an arithmetic number, because the mean of its divisors is an integer number (30809640).

Almost surely, 2^121697999 is an apocalyptic number.

121697999 is a deficient number, since it is larger than the sum of its proper divisors (1540561).

121697999 is an equidigital number, since it uses as much as digits as its factorization.

121697999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1540560.

The product of its digits is 551124, while the sum is 53.

The square root of 121697999 is about 11031.6816034547. The cubic root of 121697999 is about 495.5579858846.

The spelling of 121697999 in words is "one hundred twenty-one million, six hundred ninety-seven thousand, nine hundred ninety-nine".