121947918 has 8 divisors (see below), whose sum is σ = 243895848. Its totient is φ = 40649304.

The previous prime is 121947913. The next prime is 121947923. The reversal of 121947918 is 819749121.

It is an interprime number because it is at equal distance from previous prime (121947913) and next prime (121947923).

It is a sphenic number, since it is the product of 3 distinct primes.

121947918 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 121947918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121947913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10162321 + ... + 10162332.

It is an arithmetic number, because the mean of its divisors is an integer number (30486981).

Almost surely, 2^121947918 is an apocalyptic number.

121947918 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

121947918 is a wasteful number, since it uses less digits than its factorization.

121947918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20324658.

The product of its digits is 36288, while the sum is 42.

The square root of 121947918 is about 11043.0031241506. The cubic root of 121947918 is about 495.8969798831.

The spelling of 121947918 in words is "one hundred twenty-one million, nine hundred forty-seven thousand, nine hundred eighteen".