1401664 has 42 divisors (see below), whose sum is σ = 3074162. Its totient is φ = 633600.

The previous prime is 1401641. The next prime is 1401679. The reversal of 1401664 is 4661041.

It can be written as a sum of positive squares in only one way, i.e., 774400 + 627264 = 880^2 + 792^2 .

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7654 + ... + 7834.

2^1401664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1401664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1537081).

1401664 is an abundant number, since it is smaller than the sum of its proper divisors (1672498).

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

1401664 is a wasteful number, since it uses less digits than its factorization.

1401664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215 (or 194 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 1401664 is about 1183.9189161425. The cubic root of 1401664 is about 111.9131980505.

The spelling of 1401664 in words is "one million, four hundred one thousand, six hundred sixty-four".