71521225 has 12 divisors (see below), whose sum is σ = 93354640. Its totient is φ = 54205200.

The previous prime is 71521217. The next prime is 71521249. The reversal of 71521225 is 52212517.

71521225 = 126² + 127² + ... + 600².

It is not a de Polignac number, because 71521225 - 2³ = 71521217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 71521225.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 74811 + ... + 75760.

Almost surely, 2^71521225 is an apocalyptic number.

It is an amenable number.

71521225 is a deficient number, since it is larger than the sum of its proper divisors (21833415).

71521225 is a wasteful number, since it uses less digits than its factorization.

71521225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150600 (or 150595 counting only the distinct ones).

The product of its digits is 1400, while the sum is 25.

The square root of 71521225 is about 8457.0222300760. The cubic root of 71521225 is about 415.0925907500.

The spelling of 71521225 in words is "seventy-one million, five hundred twenty-one thousand, two hundred twenty-five".