155057221001 has 4 divisors (see below), whose sum is σ = 155869039104. Its totient is φ = 154245402900.

The previous prime is 155057220971. The next prime is 155057221013. The reversal of 155057221001 is 100122750551.

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: 100122750551 = 827 ⋅121067413.

It is a cyclic number.

It is not a de Polignac number, because 155057221001 - 2³⁴ = 137877351817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155057221801) 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, 405908765 + ... + 405909146.

It is an arithmetic number, because the mean of its divisors is an integer number (38967259776).

Almost surely, 2^155057221001 is an apocalyptic number.

It is an amenable number.

155057221001 is a deficient number, since it is larger than the sum of its proper divisors (811818103).

155057221001 is an equidigital number, since it uses as much as digits as its factorization.

155057221001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811818102.

The product of its (nonzero) digits is 3500, while the sum is 29.

Adding to 155057221001 its reverse (100122750551), we get a palindrome (255179971552).

The spelling of 155057221001 in words is "one hundred fifty-five billion, fifty-seven million, two hundred twenty-one thousand, one".