121278731 has 16 divisors (see below), whose sum is σ = 147248640. Its totient is φ = 97511040.

The previous prime is 121278713. The next prime is 121278737. The reversal of 121278731 is 137872121.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121278731 is a prime.

It is a super-2 number, since 2×121278731² = 29417061185940722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121278737) 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 15 ways as a sum of consecutive naturals, for example, 37850 + ... + 40928.

It is an arithmetic number, because the mean of its divisors is an integer number (9203040).

Almost surely, 2^121278731 is an apocalyptic number.

121278731 is a deficient number, since it is larger than the sum of its proper divisors (25969909).

121278731 is a wasteful number, since it uses less digits than its factorization.

121278731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3434.

The product of its digits is 4704, while the sum is 32.

The square root of 121278731 is about 11012.6623030038. The cubic root of 121278731 is about 494.9882403763.

The spelling of 121278731 in words is "one hundred twenty-one million, two hundred seventy-eight thousand, seven hundred thirty-one".