21401012 has 6 divisors (see below), whose sum is σ = 37451778. Its totient is φ = 10700504.

The previous prime is 21400997. The next prime is 21401047. The reversal of 21401012 is 21010412.

It can be written as a sum of positive squares in only one way, i.e., 17255716 + 4145296 = 4154^2 + 2036^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21400984 and 21401002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2675123 + ... + 2675130.

It is an arithmetic number, because the mean of its divisors is an integer number (6241963).

Almost surely, 2^21401012 is an apocalyptic number.

It is an amenable number.

21401012 is a deficient number, since it is larger than the sum of its proper divisors (16050766).

21401012 is a wasteful number, since it uses less digits than its factorization.

21401012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5350257 (or 5350255 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 21401012 is about 4626.1227826334. The cubic root of 21401012 is about 277.6374861829.

Adding to 21401012 its reverse (21010412), we get a palindrome (42411424).

The spelling of 21401012 in words is "twenty-one million, four hundred one thousand, twelve".