29999921 has 8 divisors (see below), whose sum is σ = 34429824. Its totient is φ = 25606080.

The previous prime is 29999903. The next prime is 29999923. The reversal of 29999921 is 12999992.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 29999921 - 2¹⁴ = 29983537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 29999921.

It is not an unprimeable number, because it can be changed into a prime (29999923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7205 + ... + 10578.

It is an arithmetic number, because the mean of its divisors is an integer number (4303728).

Almost surely, 2^29999921 is an apocalyptic number.

It is an amenable number.

29999921 is a deficient number, since it is larger than the sum of its proper divisors (4429903).

29999921 is a wasteful number, since it uses less digits than its factorization.

29999921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18031.

The product of its digits is 236196, while the sum is 50.

The square root of 29999921 is about 5477.2183633666. The cubic root of 29999921 is about 310.7229778492.

The spelling of 29999921 in words is "twenty-nine million, nine hundred ninety-nine thousand, nine hundred twenty-one".