1213535501 has 4 divisors (see below), whose sum is σ = 1216156992. Its totient is φ = 1210914012.

The previous prime is 1213535461. The next prime is 1213535513. The reversal of 1213535501 is 1055353121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1055353121 = 5821 ⋅181301.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1213535501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213535581) 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, 1310051 + ... + 1310976.

It is an arithmetic number, because the mean of its divisors is an integer number (304039248).

Almost surely, 2^1213535501 is an apocalyptic number.

It is an amenable number.

1213535501 is a deficient number, since it is larger than the sum of its proper divisors (2621491).

1213535501 is an equidigital number, since it uses as much as digits as its factorization.

1213535501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2621490.

The product of its (nonzero) digits is 2250, while the sum is 26.

The square root of 1213535501 is about 34835.8364475435. The cubic root of 1213535501 is about 1066.6390892067.

Adding to 1213535501 its reverse (1055353121), we get a palindrome (2268888622).

The spelling of 1213535501 in words is "one billion, two hundred thirteen million, five hundred thirty-five thousand, five hundred one".