121705668 has 72 divisors (see below), whose sum is σ = 352946048. Its totient is φ = 34639488.

The previous prime is 121705657. The next prime is 121705679. The reversal of 121705668 is 866507121.

121705668 is a `hidden beast` number, since 1 + 21 + 70 + 566 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (121705657) and next prime (121705679).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 78105 + ... + 79647.

Almost surely, 2^121705668 is an apocalyptic number.

121705668 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121705668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (176473024).

121705668 is an abundant number, since it is smaller than the sum of its proper divisors (231240380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121705668 is a wasteful number, since it uses less digits than its factorization.

121705668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1873 (or 1868 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 121705668 is about 11032.0291877786. The cubic root of 121705668 is about 495.5683951337.

The spelling of 121705668 in words is "one hundred twenty-one million, seven hundred five thousand, six hundred sixty-eight".