121663729 has 16 divisors (see below), whose sum is σ = 138600000. Its totient is φ = 105779520.

The previous prime is 121663699. The next prime is 121663739. The reversal of 121663729 is 927366121.

It is not a de Polignac number, because 121663729 - 2⁵ = 121663697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121663739) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33022 + ... + 36520.

It is an arithmetic number, because the mean of its divisors is an integer number (8662500).

Almost surely, 2^121663729 is an apocalyptic number.

It is an amenable number.

121663729 is a deficient number, since it is larger than the sum of its proper divisors (16936271).

121663729 is a wasteful number, since it uses less digits than its factorization.

121663729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3648.

The product of its digits is 27216, while the sum is 37.

The square root of 121663729 is about 11030.1282404150. The cubic root of 121663729 is about 495.5114653538.

The spelling of 121663729 in words is "one hundred twenty-one million, six hundred sixty-three thousand, seven hundred twenty-nine".