65115515 has 16 divisors (see below), whose sum is σ = 79691040. Its totient is φ = 51068160.

The previous prime is 65115511. The next prime is 65115517. The reversal of 65115515 is 51551156.

It is a happy number.

It is not a de Polignac number, because 65115515 - 2² = 65115511 is a prime.

It is not an unprimeable number, because it can be changed into a prime (65115511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57737 + ... + 58853.

It is an arithmetic number, because the mean of its divisors is an integer number (4980690).

Almost surely, 2^65115515 is an apocalyptic number.

65115515 is a deficient number, since it is larger than the sum of its proper divisors (14575525).

65115515 is a wasteful number, since it uses less digits than its factorization.

65115515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1342.

The product of its digits is 3750, while the sum is 29.

The square root of 65115515 is about 8069.4185044525. The cubic root of 65115515 is about 402.3106165111.

It can be divided in two parts, 651 and 15515, that multiplied together give a triangular number (10100265 = T₄₄₉₄).

The spelling of 65115515 in words is "sixty-five million, one hundred fifteen thousand, five hundred fifteen".