21056125461 has 8 divisors (see below), whose sum is σ = 32085524544. Its totient is φ = 12032071680.

The previous prime is 21056125457. The next prime is 21056125469. The reversal of 21056125461 is 16452165012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21056125461 - 2² = 21056125457 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21056125469) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 501336300 + ... + 501336341.

It is an arithmetic number, because the mean of its divisors is an integer number (4010690568).

Almost surely, 2^21056125461 is an apocalyptic number.

21056125461 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21056125461 is a deficient number, since it is larger than the sum of its proper divisors (11029399083).

21056125461 is a wasteful number, since it uses less digits than its factorization.

21056125461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002672651.

The product of its (nonzero) digits is 14400, while the sum is 33.

The spelling of 21056125461 in words is "twenty-one billion, fifty-six million, one hundred twenty-five thousand, four hundred sixty-one".