29972421 has 12 divisors (see below), whose sum is σ = 43482348. Its totient is φ = 19894464.

The previous prime is 29972389. The next prime is 29972477. The reversal of 29972421 is 12427992.

It can be written as a sum of positive squares in 2 ways, for example, as 2030625 + 27941796 = 1425^2 + 5286^2 .

It is not a de Polignac number, because 29972421 - 2⁵ = 29972389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (29972491) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5050 + ... + 9243.

It is an arithmetic number, because the mean of its divisors is an integer number (3623529).

Almost surely, 2^29972421 is an apocalyptic number.

It is an amenable number.

29972421 is a deficient number, since it is larger than the sum of its proper divisors (13509927).

29972421 is a wasteful number, since it uses less digits than its factorization.

29972421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14532 (or 14529 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 29972421 is about 5474.7073894410. The cubic root of 29972421 is about 310.6280054417.

The spelling of 29972421 in words is "twenty-nine million, nine hundred seventy-two thousand, four hundred twenty-one".