101555512421 has 4 divisors (see below), whose sum is σ = 110787831744. Its totient is φ = 92323193100.

The previous prime is 101555512417. The next prime is 101555512451. The reversal of 101555512421 is 124215555101.

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.

It is a cyclic number.

It is not a de Polignac number, because 101555512421 - 2² = 101555512417 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 (101555512451) 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, 4616159645 + ... + 4616159666.

It is an arithmetic number, because the mean of its divisors is an integer number (27696957936).

Almost surely, 2^101555512421 is an apocalyptic number.

101555512421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

101555512421 is a deficient number, since it is larger than the sum of its proper divisors (9232319323).

101555512421 is an equidigital number, since it uses as much as digits as its factorization.

101555512421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9232319322.

The product of its (nonzero) digits is 10000, while the sum is 32.

The spelling of 101555512421 in words is "one hundred one billion, five hundred fifty-five million, five hundred twelve thousand, four hundred twenty-one".