264621640 has 16 divisors (see below), whose sum is σ = 595398780. Its totient is φ = 105848640.

The previous prime is 264621587. The next prime is 264621649. The reversal of 264621640 is 46126462.

It can be written as a sum of positive squares in 2 ways, for example, as 260693316 + 3928324 = 16146^2 + 1982^2 .

It is a super-2 number, since 2×264621640² = 140049224712579200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (264621649) 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, 3307731 + ... + 3307810.

Almost surely, 2^264621640 is an apocalyptic number.

264621640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

264621640 is an abundant number, since it is smaller than the sum of its proper divisors (330777140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

264621640 is a wasteful number, since it uses less digits than its factorization.

264621640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6615552 (or 6615548 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 31.

The square root of 264621640 is about 16267.1952099924. The cubic root of 264621640 is about 642.0099893957.

The spelling of 264621640 in words is "two hundred sixty-four million, six hundred twenty-one thousand, six hundred forty".