1020155550 has 144 divisors (see below), whose sum is σ = 2725821072. Its totient is φ = 252416000.

The previous prime is 1020155531. The next prime is 1020155597. The reversal of 1020155550 is 555510201.

It is a self number, because there is not a number n which added to its sum of digits gives 1020155550.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 4378234 + ... + 4378466.

It is an arithmetic number, because the mean of its divisors is an integer number (18929313).

Almost surely, 2^1020155550 is an apocalyptic number.

1020155550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1020155550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1362910536).

1020155550 is an abundant number, since it is smaller than the sum of its proper divisors (1705665522).

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

1020155550 is a wasteful number, since it uses less digits than its factorization.

1020155550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 1250, while the sum is 24.

The square root of 1020155550 is about 31939.8739822185. The cubic root of 1020155550 is about 1006.6738769469.

Adding to 1020155550 its reverse (555510201), we get a palindrome (1575665751).

The spelling of 1020155550 in words is "one billion, twenty million, one hundred fifty-five thousand, five hundred fifty".