71521479225 has 189 divisors, whose sum is σ = 155226866463. Its totient is φ = 32580001440.

The previous prime is 71521479217. The next prime is 71521479257. The reversal of 71521479225 is 52297412517.

The square root of 71521479225 is 267435.

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

71521479225 is a `hidden beast` number, since 7 + 152 + 1 + 479 + 2 + 25 = 666.

It can be written as a sum of positive squares in only one way, i.e., 25747732521 + 45773746704 = 160461^2 + 213948^2 .

It is a tau number, because it is divible by the number of its divisors (189).

It is not a de Polignac number, because 71521479225 - 2³ = 71521479217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 188 ways as a sum of consecutive naturals, for example, 252725934 + ... + 252726216.

Almost surely, 2^71521479225 is an apocalyptic number.

71521479225 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

71521479225 is the 267435-th square number.

71521479225 is the 133718-th centered octagonal number.

It is an amenable number.

71521479225 is an abundant number, since it is smaller than the sum of its proper divisors (83705387238).

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

71521479225 is an frugal number, since it uses more digits than its factorization.

71521479225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608 (or 298 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The spelling of 71521479225 in words is "seventy-one billion, five hundred twenty-one million, four hundred seventy-nine thousand, two hundred twenty-five".