121151988 has 36 divisors (see below), whose sum is σ = 307953828. Its totient is φ = 40158720.

The previous prime is 121151969. The next prime is 121151993. The reversal of 121151988 is 889151121.

It can be written as a sum of positive squares in 2 ways, for example, as 26440164 + 94711824 = 5142^2 + 9732^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2781 + ... + 15812.

It is an arithmetic number, because the mean of its divisors is an integer number (8554273).

Almost surely, 2^121151988 is an apocalyptic number.

121151988 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

121151988 is an abundant number, since it is smaller than the sum of its proper divisors (186801840).

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

121151988 is a wasteful number, since it uses less digits than its factorization.

121151988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18784 (or 18779 counting only the distinct ones).

The product of its digits is 5760, while the sum is 36.

The square root of 121151988 is about 11006.9063773614. The cubic root of 121151988 is about 494.8157502207.

The spelling of 121151988 in words is "one hundred twenty-one million, one hundred fifty-one thousand, nine hundred eighty-eight".