71956453009 has 9 divisors (see below), whose sum is σ = 83706629691. Its totient is φ = 61675350240.

The previous prime is 71956453001. The next prime is 71956453013. The reversal of 71956453009 is 90035465917.

The square root of 71956453009 is 268247.

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

It can be written as a sum of positive squares in only one way, i.e., 44480075409 + 27476377600 = 210903^2 + 165760^2 .

It is not a de Polignac number, because 71956453009 - 2³ = 71956453001 is a prime.

It is a super-2 number, since 2×71956453009² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71956453001) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1858569 + ... + 1896889.

Almost surely, 2^71956453009 is an apocalyptic number.

71956453009 is the 268247-th square number.

71956453009 is the 134124-th centered octagonal number.

It is an amenable number.

71956453009 is a deficient number, since it is larger than the sum of its proper divisors (11750176682).

71956453009 is an frugal number, since it uses more digits than its factorization.

71956453009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76656 (or 38328 counting only the distinct ones).

The product of its (nonzero) digits is 1020600, while the sum is 49.

Multiplying 71956453009 by its sum of digits (49), we get a square (3525866197441 = 1877729²).

71956453009 divided by its sum of digits (49) gives a square (1468499041 = 38321²).

The spelling of 71956453009 in words is "seventy-one billion, nine hundred fifty-six million, four hundred fifty-three thousand, nine".