21942480 has 160 divisors (see below), whose sum is σ = 80066304. Its totient is φ = 4866048.

The previous prime is 21942469. The next prime is 21942491. The reversal of 21942480 is 8424912.

It is an interprime number because it is at equal distance from previous prime (21942469) and next prime (21942491).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61984 + ... + 62336.

Almost surely, 2^21942480 is an apocalyptic number.

21942480 is a gapful number since it is divisible by the number (20) 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 21942480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40033152).

21942480 is an abundant number, since it is smaller than the sum of its proper divisors (58123824).

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

21942480 is a wasteful number, since it uses less digits than its factorization.

21942480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 413 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 21942480 is about 4684.2800941020. The cubic root of 21942480 is about 279.9595179570.

It can be divided in two parts, 21942 and 480, that added together give a palindrome (22422).

The spelling of 21942480 in words is "twenty-one million, nine hundred forty-two thousand, four hundred eighty".