55777520 has 40 divisors (see below), whose sum is σ = 129999120. Its totient is φ = 22256640.

The previous prime is 55777517. The next prime is 55777523. The reversal of 55777520 is 2577755.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (55777517) and next prime (55777523).

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×55777520² = 6222263474700800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55777523) 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, 54776 + ... + 55784.

It is an arithmetic number, because the mean of its divisors is an integer number (3249978).

Almost surely, 2^55777520 is an apocalyptic number.

It is an amenable number.

55777520 is an abundant number, since it is smaller than the sum of its proper divisors (74221600).

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

55777520 is a wasteful number, since it uses less digits than its factorization.

55777520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1713 (or 1707 counting only the distinct ones).

The product of its (nonzero) digits is 85750, while the sum is 38.

The square root of 55777520 is about 7468.4349096715. The cubic root of 55777520 is about 382.0789106281.

The spelling of 55777520 in words is "fifty-five million, seven hundred seventy-seven thousand, five hundred twenty".