1691265625 has 63 divisors (see below), whose sum is σ = 2512643619. Its totient is φ = 1135050000.

The previous prime is 1691265619. The next prime is 1691265661. The reversal of 1691265625 is 5265621961.

The square root of 1691265625 is 41125.

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

It can be written as a sum of positive squares in 3 ways, for example, as 1481711049 + 209554576 = 38493^2 + 14476^2 .

It is not a de Polignac number, because 1691265625 - 2³ = 1691265617 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 35984352 + ... + 35984398.

Almost surely, 2^1691265625 is an apocalyptic number.

1691265625 is the 41125-th square number.

1691265625 is the 20563-rd centered octagonal number.

It is an amenable number.

1691265625 is a deficient number, since it is larger than the sum of its proper divisors (821377994).

1691265625 is an frugal number, since it uses more digits than its factorization.

1691265625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138 (or 59 counting only the distinct ones).

The product of its digits is 194400, while the sum is 43.

The cubic root of 1691265625 is about 1191.4356950978.

It can be divided in two parts, 169 and 1265625, that multiplied together give a square (213890625 = 14625²).

The spelling of 1691265625 in words is "one billion, six hundred ninety-one million, two hundred sixty-five thousand, six hundred twenty-five".