29971920 has 80 divisors (see below), whose sum is σ = 101368512. Its totient is φ = 7265280.

The previous prime is 29971919. The next prime is 29971927. The reversal of 29971920 is 2917992.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (29971927) 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, 3037 + ... + 8316.

Almost surely, 2^29971920 is an apocalyptic number.

29971920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

29971920 is an abundant number, since it is smaller than the sum of its proper divisors (71396592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

29971920 is a wasteful number, since it uses less digits than its factorization.

29971920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11380 (or 11374 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 39.

The square root of 29971920 is about 5474.6616333797. The cubic root of 29971920 is about 310.6262746784.

The spelling of 29971920 in words is "twenty-nine million, nine hundred seventy-one thousand, nine hundred twenty".