29720121 has 32 divisors (see below), whose sum is σ = 42674688. Its totient is φ = 18370560.

The previous prime is 29720113. The next prime is 29720137. The reversal of 29720121 is 12102792.

It is not a de Polignac number, because 29720121 - 2³ = 29720113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 29720091 and 29720100.

It is not an unprimeable number, because it can be changed into a prime (29720191) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 306345 + ... + 306441.

It is an arithmetic number, because the mean of its divisors is an integer number (1333584).

Almost surely, 2^29720121 is an apocalyptic number.

It is an amenable number.

29720121 is a deficient number, since it is larger than the sum of its proper divisors (12954567).

29720121 is a wasteful number, since it uses less digits than its factorization.

29720121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 29720121 is about 5451.6163658130. The cubic root of 29720121 is about 309.7539532210.

The spelling of 29720121 in words is "twenty-nine million, seven hundred twenty thousand, one hundred twenty-one".