10221540 has 48 divisors (see below), whose sum is σ = 32710272. Its totient is φ = 2336256.

The previous prime is 10221521. The next prime is 10221551. The reversal of 10221540 is 4512201.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11749 + ... + 12588.

It is an arithmetic number, because the mean of its divisors is an integer number (681464).

Almost surely, 2^10221540 is an apocalyptic number.

10221540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

10221540 is an abundant number, since it is smaller than the sum of its proper divisors (22488732).

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

10221540 is a wasteful number, since it uses less digits than its factorization.

10221540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24356 (or 24354 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 10221540 is about 3197.1143238865. The cubic root of 10221540 is about 217.0228408642.

Adding to 10221540 its reverse (4512201), we get a palindrome (14733741).

The spelling of 10221540 in words is "ten million, two hundred twenty-one thousand, five hundred forty".