21890977225 has 24 divisors (see below), whose sum is σ = 29292625152. Its totient is φ = 16132603200.

The previous prime is 21890977217. The next prime is 21890977253. The reversal of 21890977225 is 52277909812.

It is a happy number.

It is not a de Polignac number, because 21890977225 - 2³ = 21890977217 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 90984 + ... + 228166.

It is an arithmetic number, because the mean of its divisors is an integer number (1220526048).

Almost surely, 2^21890977225 is an apocalyptic number.

21890977225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21890977225 is a deficient number, since it is larger than the sum of its proper divisors (7401647927).

21890977225 is a wasteful number, since it uses less digits than its factorization.

21890977225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137697 (or 137692 counting only the distinct ones).

The product of its (nonzero) digits is 1270080, while the sum is 52.

The spelling of 21890977225 in words is "twenty-one billion, eight hundred ninety million, nine hundred seventy-seven thousand, two hundred twenty-five".