21025401488 has 80 divisors (see below), whose sum is σ = 50520683136. Its totient is φ = 8254172160.

The previous prime is 21025401487. The next prime is 21025401541. The reversal of 21025401488 is 88410452012.

It is a super-2 number, since 2×21025401488² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21025401487) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135620 + ... + 245852.

Almost surely, 2^21025401488 is an apocalyptic number.

21025401488 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21025401488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25260341568).

21025401488 is an abundant number, since it is smaller than the sum of its proper divisors (29495281648).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21025401488 is a wasteful number, since it uses less digits than its factorization.

21025401488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110392 (or 110386 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 35.

The spelling of 21025401488 in words is "twenty-one billion, twenty-five million, four hundred one thousand, four hundred eighty-eight".