51220409 has 8 divisors (see below), whose sum is σ = 55776000. Its totient is φ = 46850832.

The previous prime is 51220391. The next prime is 51220417. The reversal of 51220409 is 90402215.

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 51220409 - 2¹² = 51216313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51220489) 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, 45929 + ... + 47030.

It is an arithmetic number, because the mean of its divisors is an integer number (6972000).

Almost surely, 2^51220409 is an apocalyptic number.

It is an amenable number.

51220409 is a deficient number, since it is larger than the sum of its proper divisors (4555591).

51220409 is a wasteful number, since it uses less digits than its factorization.

51220409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93007.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 51220409 is about 7156.8435081396. The cubic root of 51220409 is about 371.3764387736.

The spelling of 51220409 in words is "fifty-one million, two hundred twenty thousand, four hundred nine".