1098121572 has 18 divisors (see below), whose sum is σ = 2775807398. Its totient is φ = 366040512.

The previous prime is 1098121559. The next prime is 1098121643. The reversal of 1098121572 is 2751218901.

It is a happy number.

1098121572 is a `hidden beast` number, since 1 + 0 + 9 + 81 + 2 + 1 + 572 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1077546276 + 20575296 = 32826^2 + 4536^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 30503377 = 1098121572 / (1 + 0 + 9 + 8 + 1 + 2 + 1 + 5 + 7 + 2).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 15251653 + ... + 15251724.

Almost surely, 2^1098121572 is an apocalyptic number.

1098121572 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1098121572 is an abundant number, since it is smaller than the sum of its proper divisors (1677685826).

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

1098121572 is a wasteful number, since it uses less digits than its factorization.

1098121572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30503387 (or 30503382 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 36.

The square root of 1098121572 is about 33137.9174360731. The cubic root of 1098121572 is about 1031.6921855545.

The spelling of 1098121572 in words is "one billion, ninety-eight million, one hundred twenty-one thousand, five hundred seventy-two".