133640401 has 4 divisors (see below), whose sum is σ = 136161972. Its totient is φ = 131118832.

The previous prime is 133640399. The next prime is 133640407. The reversal of 133640401 is 104046331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 104046331 = 37 ⋅2812063.

It can be written as a sum of positive squares in 2 ways, for example, as 57532225 + 76108176 = 7585^2 + 8724^2 .

It is a cyclic number.

It is not a de Polignac number, because 133640401 - 2¹ = 133640399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133640407) 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, 1260706 + ... + 1260811.

It is an arithmetic number, because the mean of its divisors is an integer number (34040493).

Almost surely, 2^133640401 is an apocalyptic number.

It is an amenable number.

133640401 is a deficient number, since it is larger than the sum of its proper divisors (2521571).

133640401 is an equidigital number, since it uses as much as digits as its factorization.

133640401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2521570.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 133640401 is about 11560.2941571571. The cubic root of 133640401 is about 511.2648356636.

Adding to 133640401 its reverse (104046331), we get a palindrome (237686732).

The spelling of 133640401 in words is "one hundred thirty-three million, six hundred forty thousand, four hundred one".