55780390 has 32 divisors (see below), whose sum is σ = 106362720. Its totient is φ = 21003264.

The previous prime is 55780379. The next prime is 55780391. The reversal of 55780390 is 9308755.

It is a super-2 number, since 2×55780390² = 6222903817104200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55780391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32022 + ... + 33718.

It is an arithmetic number, because the mean of its divisors is an integer number (3323835).

Almost surely, 2^55780390 is an apocalyptic number.

55780390 is a deficient number, since it is larger than the sum of its proper divisors (50582330).

55780390 is a wasteful number, since it uses less digits than its factorization.

55780390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1896.

The product of its (nonzero) digits is 37800, while the sum is 37.

The square root of 55780390 is about 7468.6270491972. The cubic root of 55780390 is about 382.0854637321.

The spelling of 55780390 in words is "fifty-five million, seven hundred eighty thousand, three hundred ninety".