21259990145401 has 4 divisors (see below), whose sum is σ = 24297131594752. Its totient is φ = 18222848696052.

The previous prime is 21259990145323. The next prime is 21259990145479. The reversal of 21259990145401 is 10454109995212.

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 an interprime number because it is at equal distance from previous prime (21259990145323) and next prime (21259990145479).

It is not a de Polignac number, because 21259990145401 - 2¹³ = 21259990137209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21259990145501) 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, 1518570724665 + ... + 1518570724678.

It is an arithmetic number, because the mean of its divisors is an integer number (6074282898688).

Almost surely, 2^{21259990145401} is an apocalyptic number.

It is an amenable number.

21259990145401 is a deficient number, since it is larger than the sum of its proper divisors (3037141449351).

21259990145401 is an equidigital number, since it uses as much as digits as its factorization.

21259990145401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3037141449350.

The product of its (nonzero) digits is 1166400, while the sum is 52.

The spelling of 21259990145401 in words is "twenty-one trillion, two hundred fifty-nine billion, nine hundred ninety million, one hundred forty-five thousand, four hundred one".