1401540641 has 4 divisors (see below), whose sum is σ = 1401806484. Its totient is φ = 1401274800.

The previous prime is 1401540629. The next prime is 1401540661. The reversal of 1401540641 is 1460451041.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1056510016 + 345030625 = 32504^2 + 18575^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1401540641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1401540641.

It is not an unprimeable number, because it can be changed into a prime (1401540661) 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, 124850 + ... + 135611.

It is an arithmetic number, because the mean of its divisors is an integer number (350451621).

Almost surely, 2^1401540641 is an apocalyptic number.

It is an amenable number.

1401540641 is a deficient number, since it is larger than the sum of its proper divisors (265843).

1401540641 is an equidigital number, since it uses as much as digits as its factorization.

1401540641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265842.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 1401540641 is about 37437.1558882349. The cubic root of 1401540641 is about 1119.0991483253.

Adding to 1401540641 its reverse (1460451041), we get a palindrome (2861991682).

The spelling of 1401540641 in words is "one billion, four hundred one million, five hundred forty thousand, six hundred forty-one".