51456780 has 36 divisors (see below), whose sum is σ = 156086112. Its totient is φ = 13721760.

The previous prime is 51456749. The next prime is 51456787. The reversal of 51456780 is 8765415.

51456780 is a `hidden beast` number, since 5 + 14 + 567 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (51456787) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 142756 + ... + 143115.

Almost surely, 2^51456780 is an apocalyptic number.

It is an amenable number.

51456780 is an abundant number, since it is smaller than the sum of its proper divisors (104629332).

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

51456780 is a wasteful number, since it uses less digits than its factorization.

51456780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285886 (or 285881 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 51456780 is about 7173.3381350665. The cubic root of 51456780 is about 371.9468359682.

The spelling of 51456780 in words is "fifty-one million, four hundred fifty-six thousand, seven hundred eighty".