121156640 has 192 divisors, whose sum is σ = 338349312. Its totient is φ = 40550400.

The previous prime is 121156639. The next prime is 121156667. The reversal of 121156640 is 46651121.

121156640 = T₁₆₅ + T₁₆₆ + ... + T₉₀₀.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1659644 + ... + 1659716.

It is an arithmetic number, because the mean of its divisors is an integer number (1762236).

Almost surely, 2^121156640 is an apocalyptic number.

121156640 is a gapful number since it is divisible by the number (10) 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 121156640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169174656).

121156640 is an abundant number, since it is smaller than the sum of its proper divisors (217192672).

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

121156640 is a wasteful number, since it uses less digits than its factorization.

121156640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 121156640 is about 11007.1176971994. The cubic root of 121156640 is about 494.8220834595.

The spelling of 121156640 in words is "one hundred twenty-one million, one hundred fifty-six thousand, six hundred forty".