51229947 has 24 divisors (see below), whose sum is σ = 75208000. Its totient is φ = 30930768.

The previous prime is 51229939. The next prime is 51229961. The reversal of 51229947 is 74992215.

It is not a de Polignac number, because 51229947 - 2³ = 51229939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51229907) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29304 + ... + 31002.

Almost surely, 2^51229947 is an apocalyptic number.

51229947 is a gapful number since it is divisible by the number (57) formed by its first and last digit.

51229947 is a deficient number, since it is larger than the sum of its proper divisors (23978053).

51229947 is a wasteful number, since it uses less digits than its factorization.

51229947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1767 (or 1744 counting only the distinct ones).

The product of its digits is 45360, while the sum is 39.

The square root of 51229947 is about 7157.5098323369. The cubic root of 51229947 is about 371.3994892769.

The spelling of 51229947 in words is "fifty-one million, two hundred twenty-nine thousand, nine hundred forty-seven".