1521989145 has 12 divisors (see below), whose sum is σ = 2638114596. Its totient is φ = 811727520.

The previous prime is 1521989137. The next prime is 1521989149. The reversal of 1521989145 is 5419891251.

1521989145 is a `hidden beast` number, since 1 + 521 + 9 + 89 + 1 + 45 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1042773264 + 479215881 = 32292^2 + 21891^2 .

It is not a de Polignac number, because 1521989145 - 2³ = 1521989137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 33821981 = 1521989145 / (1 + 5 + 2 + 1 + 9 + 8 + 9 + 1 + 4 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 1521989145.

It is not an unprimeable number, because it can be changed into a prime (1521989149) 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, 16910946 + ... + 16911035.

It is an arithmetic number, because the mean of its divisors is an integer number (219842883).

Almost surely, 2^1521989145 is an apocalyptic number.

1521989145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1521989145 is a deficient number, since it is larger than the sum of its proper divisors (1116125451).

1521989145 is a wasteful number, since it uses less digits than its factorization.

1521989145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33821992 (or 33821989 counting only the distinct ones).

The product of its digits is 129600, while the sum is 45.

The square root of 1521989145 is about 39012.6792850735. The cubic root of 1521989145 is about 1150.2807493505.

The spelling of 1521989145 in words is "one billion, five hundred twenty-one million, nine hundred eighty-nine thousand, one hundred forty-five".