21420531445 has 8 divisors (see below), whose sum is σ = 26140309920. Its totient is φ = 16845977040.

The previous prime is 21420531439. The next prime is 21420531449. The reversal of 21420531445 is 54413502412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21420531445 - 2⁵ = 21420531413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21420531449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36305691 + ... + 36306280.

It is an arithmetic number, because the mean of its divisors is an integer number (3267538740).

Almost surely, 2^21420531445 is an apocalyptic number.

It is an amenable number.

21420531445 is a deficient number, since it is larger than the sum of its proper divisors (4719778475).

21420531445 is an equidigital number, since it uses as much as digits as its factorization.

21420531445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72612035.

The product of its (nonzero) digits is 19200, while the sum is 31.

The spelling of 21420531445 in words is "twenty-one billion, four hundred twenty million, five hundred thirty-one thousand, four hundred forty-five".