51209899 has 8 divisors (see below), whose sum is σ = 58393440. Its totient is φ = 44489856.

The previous prime is 51209897. The next prime is 51209941. The reversal of 51209899 is 99890215.

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 51209899 - 2¹ = 51209897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51209897) 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, 115639 + ... + 116080.

It is an arithmetic number, because the mean of its divisors is an integer number (7299180).

Almost surely, 2^51209899 is an apocalyptic number.

51209899 is a deficient number, since it is larger than the sum of its proper divisors (7183541).

51209899 is a wasteful number, since it uses less digits than its factorization.

51209899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231749.

The product of its (nonzero) digits is 58320, while the sum is 43.

The square root of 51209899 is about 7156.1092082220. The cubic root of 51209899 is about 371.3510359219.

The spelling of 51209899 in words is "fifty-one million, two hundred nine thousand, eight hundred ninety-nine".