55009890 has 48 divisors (see below), whose sum is σ = 154030968. Its totient is φ = 13540608.

The previous prime is 55009873. The next prime is 55009891. The reversal of 55009890 is 9890055.

It can be written as a sum of positive squares in 4 ways, for example, as 48399849 + 6610041 = 6957^2 + 2571^2 .

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (55009891) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22339 + ... + 24678.

Almost surely, 2^55009890 is an apocalyptic number.

55009890 is an abundant number, since it is smaller than the sum of its proper divisors (99021078).

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

55009890 is a wasteful number, since it uses less digits than its factorization.

55009890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47043 (or 47040 counting only the distinct ones).

The product of its (nonzero) digits is 16200, while the sum is 36.

The square root of 55009890 is about 7416.8652407874. The cubic root of 55009890 is about 380.3180393765.

The spelling of 55009890 in words is "fifty-five million, nine thousand, eight hundred ninety".