215440638071 has 4 divisors (see below), whose sum is σ = 220450885512. Its totient is φ = 210430390632.

The previous prime is 215440638043. The next prime is 215440638089. The reversal of 215440638071 is 170836044512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 215440638071 - 2²² = 215436443767 is a prime.

It is a super-2 number, since 2×215440638071² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215440638571) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2505123656 + ... + 2505123741.

It is an arithmetic number, because the mean of its divisors is an integer number (55112721378).

Almost surely, 2^215440638071 is an apocalyptic number.

215440638071 is a deficient number, since it is larger than the sum of its proper divisors (5010247441).

215440638071 is an equidigital number, since it uses as much as digits as its factorization.

215440638071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5010247440.

The product of its (nonzero) digits is 161280, while the sum is 41.

The spelling of 215440638071 in words is "two hundred fifteen billion, four hundred forty million, six hundred thirty-eight thousand, seventy-one".