55291890 has 16 divisors (see below), whose sum is σ = 132700608. Its totient is φ = 14744496.

The previous prime is 55291867. The next prime is 55291891. The reversal of 55291890 is 9819255.

It is not an unprimeable number, because it can be changed into a prime (55291891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 921502 + ... + 921561.

It is an arithmetic number, because the mean of its divisors is an integer number (8293788).

Almost surely, 2^55291890 is an apocalyptic number.

55291890 is an abundant number, since it is smaller than the sum of its proper divisors (77408718).

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

55291890 is a wasteful number, since it uses less digits than its factorization.

55291890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1843073.

The product of its (nonzero) digits is 32400, while the sum is 39.

The square root of 55291890 is about 7435.8516660837. The cubic root of 55291890 is about 380.9668132652.

The spelling of 55291890 in words is "fifty-five million, two hundred ninety-one thousand, eight hundred ninety".