29971431 has 32 divisors (see below), whose sum is σ = 51002880. Its totient is φ = 17039808.

The previous prime is 29971397. The next prime is 29971433. The reversal of 29971431 is 13417992.

It is a de Polignac number, because none of the positive numbers 2^k-29971431 is a prime.

It is a super-2 number, since 2×29971431² = 1796573352375522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (29971433) 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, 65355 + ... + 65811.

It is an arithmetic number, because the mean of its divisors is an integer number (1593840).

Almost surely, 2^29971431 is an apocalyptic number.

29971431 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

29971431 is a deficient number, since it is larger than the sum of its proper divisors (21031449).

29971431 is a wasteful number, since it uses less digits than its factorization.

29971431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820 (or 814 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 29971431 is about 5474.6169729032. The cubic root of 29971431 is about 310.6245853519.

The spelling of 29971431 in words is "twenty-nine million, nine hundred seventy-one thousand, four hundred thirty-one".