71220513 has 32 divisors (see below), whose sum is σ = 119612416. Its totient is φ = 36687168.

The previous prime is 71220511. The next prime is 71220521. The reversal of 71220513 is 31502217.

It is not a de Polignac number, because 71220513 - 2¹ = 71220511 is a prime.

It is a super-2 number, since 2×71220513² = 10144722943966338, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 71220513.

It is not an unprimeable number, because it can be changed into a prime (71220511) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8706 + ... + 14772.

It is an arithmetic number, because the mean of its divisors is an integer number (3737888).

Almost surely, 2^71220513 is an apocalyptic number.

It is an amenable number.

71220513 is a deficient number, since it is larger than the sum of its proper divisors (48391903).

71220513 is a wasteful number, since it uses less digits than its factorization.

71220513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6133.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 71220513 is about 8439.2246681789. The cubic root of 71220513 is about 414.5100192900.

The spelling of 71220513 in words is "seventy-one million, two hundred twenty thousand, five hundred thirteen".