65421915 has 32 divisors (see below), whose sum is σ = 113762880. Its totient is φ = 31911936.

The previous prime is 65421911. The next prime is 65421929. The reversal of 65421915 is 51912456.

It is not a de Polignac number, because 65421915 - 2² = 65421911 is a prime.

It is not an unprimeable number, because it can be changed into a prime (65421911) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20551 + ... + 23519.

It is an arithmetic number, because the mean of its divisors is an integer number (3555090).

Almost surely, 2^65421915 is an apocalyptic number.

65421915 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

65421915 is a deficient number, since it is larger than the sum of its proper divisors (48340965).

65421915 is a wasteful number, since it uses less digits than its factorization.

65421915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3103.

The product of its digits is 10800, while the sum is 33.

The square root of 65421915 is about 8088.3814821013. The cubic root of 65421915 is about 402.9406513633.

The spelling of 65421915 in words is "sixty-five million, four hundred twenty-one thousand, nine hundred fifteen".