1401605138209 has 2 divisors, whose sum is σ = 1401605138210. Its totient is φ = 1401605138208.

The previous prime is 1401605138201. The next prime is 1401605138249. The reversal of 1401605138209 is 9028315061041.

It is an a-pointer prime, because the next prime (1401605138249) can be obtained adding 1401605138209 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1128183865600 + 273421272609 = 1062160^2 + 522897^2 .

It is a cyclic number.

It is not a de Polignac number, because 1401605138209 - 2³ = 1401605138201 is a prime.

It is not a weakly prime, because it can be changed into another prime (1401605138201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 700802569104 + 700802569105.

It is an arithmetic number, because the mean of its divisors is an integer number (700802569105).

Almost surely, 2^{1401605138209} is an apocalyptic number.

It is an amenable number.

1401605138209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1401605138209 is an equidigital number, since it uses as much as digits as its factorization.

1401605138209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 1401605138209 in words is "one trillion, four hundred one billion, six hundred five million, one hundred thirty-eight thousand, two hundred nine".