997155550 has 24 divisors (see below), whose sum is σ = 1904840136. Its totient is φ = 388081440.

The previous prime is 997155521. The next prime is 997155557. The reversal of 997155550 is 55551799.

It is a self number, because there is not a number n which added to its sum of digits gives 997155550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997155557) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 267652 + ... + 271351.

It is an arithmetic number, because the mean of its divisors is an integer number (79368339).

Almost surely, 2^997155550 is an apocalyptic number.

997155550 is a deficient number, since it is larger than the sum of its proper divisors (907684586).

997155550 is a wasteful number, since it uses less digits than its factorization.

997155550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539052 (or 539047 counting only the distinct ones).

The product of its (nonzero) digits is 354375, while the sum is 46.

The square root of 997155550 is about 31577.7698705909. The cubic root of 997155550 is about 999.0509495883.

The spelling of 997155550 in words is "nine hundred ninety-seven million, one hundred fifty-five thousand, five hundred fifty".