51216402 has 16 divisors (see below), whose sum is σ = 105737472. Its totient is φ = 16521360.

The previous prime is 51216401. The next prime is 51216409. The reversal of 51216402 is 20461215.

It is not an unprimeable number, because it can be changed into a prime (51216401) 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, 137493 + ... + 137864.

It is an arithmetic number, because the mean of its divisors is an integer number (6608592).

Almost surely, 2^51216402 is an apocalyptic number.

51216402 is an abundant number, since it is smaller than the sum of its proper divisors (54521070).

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

51216402 is a wasteful number, since it uses less digits than its factorization.

51216402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275393.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 51216402 is about 7156.5635608160. The cubic root of 51216402 is about 371.3667541952.

Adding to 51216402 its reverse (20461215), we get a palindrome (71677617).

The spelling of 51216402 in words is "fifty-one million, two hundred sixteen thousand, four hundred two".