51261420 has 48 divisors (see below), whose sum is σ = 164037888. Its totient is φ = 11716800.

The previous prime is 51261401. The next prime is 51261451. The reversal of 51261420 is 2416215.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60606 + ... + 61445.

It is an arithmetic number, because the mean of its divisors is an integer number (3417456).

Almost surely, 2^51261420 is an apocalyptic number.

It is an amenable number.

51261420 is an abundant number, since it is smaller than the sum of its proper divisors (112776468).

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

51261420 is a wasteful number, since it uses less digits than its factorization.

51261420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122070 (or 122068 counting only the distinct ones).

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

The square root of 51261420 is about 7159.7080946083. The cubic root of 51261420 is about 371.4755298477.

Adding to 51261420 its reverse (2416215), we get a palindrome (53677635).

It can be divided in two parts, 51261 and 420, that added together give a triangular number (51681 = T₃₂₁).

The spelling of 51261420 in words is "fifty-one million, two hundred sixty-one thousand, four hundred twenty".