87780215 has 4 divisors (see below), whose sum is σ = 105336264. Its totient is φ = 70224168.

The previous prime is 87780193. The next prime is 87780223. The reversal of 87780215 is 51208778.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51208778 = 2 ⋅25604389.

It is a cyclic number.

It is not a de Polignac number, because 87780215 - 2⁶ = 87780151 is a prime.

It is a super-2 number, since 2×87780215² = 15410732290892450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8778017 + ... + 8778026.

It is an arithmetic number, because the mean of its divisors is an integer number (26334066).

Almost surely, 2^87780215 is an apocalyptic number.

87780215 is a deficient number, since it is larger than the sum of its proper divisors (17556049).

87780215 is a wasteful number, since it uses less digits than its factorization.

87780215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17556048.

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 87780215 is about 9369.1096161802. The cubic root of 87780215 is about 444.4254082935.

The spelling of 87780215 in words is "eighty-seven million, seven hundred eighty thousand, two hundred fifteen".