407721664 has 28 divisors (see below), whose sum is σ = 924655504. Its totient is φ = 174737664.

The previous prime is 407721661. The next prime is 407721719. The reversal of 407721664 is 466127704.

It is a tau number, because it is divible by the number of its divisors (28).

It is a super-3 number, since 3×407721664³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (407721661) 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, 454599 + ... + 455494.

Almost surely, 2^407721664 is an apocalyptic number.

It is an amenable number.

407721664 is an abundant number, since it is smaller than the sum of its proper divisors (516933840).

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

407721664 is an equidigital number, since it uses as much as digits as its factorization.

407721664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 910112 (or 910102 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 37.

The square root of 407721664 is about 20192.1188586042. The cubic root of 407721664 is about 741.5172570696.

It can be divided in two parts, 40772 and 1664, that added together give a square (42436 = 206²).

The spelling of 407721664 in words is "four hundred seven million, seven hundred twenty-one thousand, six hundred sixty-four".