55457780 has 48 divisors (see below), whose sum is σ = 133902720. Its totient is φ = 18899328.

The previous prime is 55457777. The next prime is 55457813. The reversal of 55457780 is 8775455.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a congruent number.

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, 23954 + ... + 26166.

It is an arithmetic number, because the mean of its divisors is an integer number (2789640).

Almost surely, 2^55457780 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55457780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66951360).

55457780 is an abundant number, since it is smaller than the sum of its proper divisors (78444940).

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

55457780 is a wasteful number, since it uses less digits than its factorization.

55457780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2408 (or 2406 counting only the distinct ones).

The product of its (nonzero) digits is 196000, while the sum is 41.

The square root of 55457780 is about 7446.9980529070. The cubic root of 55457780 is about 381.3474325914.

The spelling of 55457780 in words is "fifty-five million, four hundred fifty-seven thousand, seven hundred eighty".