1491561477025 has 27 divisors (see below), whose sum is σ = 1890089027769. Its totient is φ = 1167636182880.

The previous prime is 1491561476969. The next prime is 1491561477031. The reversal of 1491561477025 is 5207741651941.

The square root of 1491561477025 is 1221295.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 50197954401 + 1441363522624 = 224049^2 + 1200568^2 .

It is not a de Polignac number, because 1491561477025 - 2¹³ = 1491561468833 is a prime.

It is a super-3 number, since 3×1491561477025³ (a number of 37 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 287001727 + ... + 287006923.

Almost surely, 2^{1491561477025} is an apocalyptic number.

1491561477025 is the 1221295-th square number.

1491561477025 is the 610648-th centered octagonal number.

It is an amenable number.

1491561477025 is a deficient number, since it is larger than the sum of its proper divisors (398527550744).

1491561477025 is an frugal number, since it uses more digits than its factorization.

1491561477025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10498 (or 5249 counting only the distinct ones).

The product of its (nonzero) digits is 2116800, while the sum is 52.

The spelling of 1491561477025 in words is "one trillion, four hundred ninety-one billion, five hundred sixty-one million, four hundred seventy-seven thousand, twenty-five".