21055540654 has 16 divisors (see below), whose sum is σ = 32701431600. Its totient is φ = 10155708864.

The previous prime is 21055540651. The next prime is 21055540657. The reversal of 21055540654 is 45604555012.

It is an interprime number because it is at equal distance from previous prime (21055540651) and next prime (21055540657).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21055540651) 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, 95292 + ... + 226255.

It is an arithmetic number, because the mean of its divisors is an integer number (2043839475).

Almost surely, 2^21055540654 is an apocalyptic number.

21055540654 is a deficient number, since it is larger than the sum of its proper divisors (11645890946).

21055540654 is a wasteful number, since it uses less digits than its factorization.

21055540654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322707.

The product of its (nonzero) digits is 120000, while the sum is 37.

The spelling of 21055540654 in words is "twenty-one billion, fifty-five million, five hundred forty thousand, six hundred fifty-four".