21012376 has 72 divisors (see below), whose sum is σ = 50489460. Its totient is φ = 8168160.

The previous prime is 21012373. The next prime is 21012401. The reversal of 21012376 is 67321012.

21012376 = T₃₉₈ + T₃₉₉ + ... + T₅₇₃.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012371) by changing a digit.

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 17 ways as a sum of consecutive naturals, for example, 47211 + ... + 47653.

Almost surely, 2^21012376 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25244730).

21012376 is an abundant number, since it is smaller than the sum of its proper divisors (29477084).

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

21012376 is a wasteful number, since it uses less digits than its factorization.

21012376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485 (or 463 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 21012376 is about 4583.9258283703. The cubic root of 21012376 is about 275.9466045275.

Adding to 21012376 its reverse (67321012), we get a palindrome (88333388).

The spelling of 21012376 in words is "twenty-one million, twelve thousand, three hundred seventy-six".