215220413 has 4 divisors (see below), whose sum is σ = 215997660. Its totient is φ = 214443168.

The previous prime is 215220409. The next prime is 215220431. The reversal of 215220413 is 314022512.

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

It can be written as a sum of positive squares in 2 ways, for example, as 55905529 + 159314884 = 7477^2 + 12622^2 .

It is a cyclic number.

It is not a de Polignac number, because 215220413 - 2² = 215220409 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 (215220433) 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, 388208 + ... + 388761.

It is an arithmetic number, because the mean of its divisors is an integer number (53999415).

Almost surely, 2^215220413 is an apocalyptic number.

It is an amenable number.

215220413 is a deficient number, since it is larger than the sum of its proper divisors (777247).

215220413 is an equidigital number, since it uses as much as digits as its factorization.

215220413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 777246.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 215220413 is about 14670.3923942068. The cubic root of 215220413 is about 599.2772900185.

Adding to 215220413 its reverse (314022512), we get a palindrome (529242925).

The spelling of 215220413 in words is "two hundred fifteen million, two hundred twenty thousand, four hundred thirteen".