121281765 has 64 divisors (see below), whose sum is σ = 221405184. Its totient is φ = 56160000.

The previous prime is 121281763. The next prime is 121281767. The reversal of 121281765 is 567182121.

It is an interprime number because it is at equal distance from previous prime (121281763) and next prime (121281767).

It is not a de Polignac number, because 121281765 - 2¹ = 121281763 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121281763) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 669975 + ... + 670155.

It is an arithmetic number, because the mean of its divisors is an integer number (3459456).

Almost surely, 2^121281765 is an apocalyptic number.

121281765 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121281765 is a deficient number, since it is larger than the sum of its proper divisors (100123419).

121281765 is a wasteful number, since it uses less digits than its factorization.

121281765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362.

The product of its digits is 6720, while the sum is 33.

The square root of 121281765 is about 11012.8000526660. The cubic root of 121281765 is about 494.9923680080.

The spelling of 121281765 in words is "one hundred twenty-one million, two hundred eighty-one thousand, seven hundred sixty-five".