121900890 has 16 divisors (see below), whose sum is σ = 292562208. Its totient is φ = 32506896.

The previous prime is 121900879. The next prime is 121900907. The reversal of 121900890 is 98009121.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 4063363 = 121900890 / (1 + 2 + 1 + 9 + 0 + 0 + 8 + 9 + 0).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2031652 + ... + 2031711.

It is an arithmetic number, because the mean of its divisors is an integer number (18285138).

Almost surely, 2^121900890 is an apocalyptic number.

121900890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121900890 is an abundant number, since it is smaller than the sum of its proper divisors (170661318).

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

121900890 is a wasteful number, since it uses less digits than its factorization.

121900890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4063373.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 121900890 is about 11040.8736067396. The cubic root of 121900890 is about 495.8332257766.

The spelling of 121900890 in words is "one hundred twenty-one million, nine hundred thousand, eight hundred ninety".