215642142077 has 4 divisors (see below), whose sum is σ = 215859743616. Its totient is φ = 215424540540.

The previous prime is 215642142073. The next prime is 215642142083. The reversal of 215642142077 is 770241246512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 215642142077 - 2² = 215642142073 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215642142071) 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, 108799283 + ... + 108801264.

It is an arithmetic number, because the mean of its divisors is an integer number (53964935904).

Almost surely, 2^215642142077 is an apocalyptic number.

It is an amenable number.

215642142077 is a deficient number, since it is larger than the sum of its proper divisors (217601539).

215642142077 is an equidigital number, since it uses as much as digits as its factorization.

215642142077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217601538.

The product of its (nonzero) digits is 188160, while the sum is 41.

Adding to 215642142077 its reverse (770241246512), we get a palindrome (985883388589).

The spelling of 215642142077 in words is "two hundred fifteen billion, six hundred forty-two million, one hundred forty-two thousand, seventy-seven".