21621402477270 has 96 divisors (see below), whose sum is σ = 56301800615424. Its totient is φ = 5756874120000.

The previous prime is 21621402477263. The next prime is 21621402477289. The reversal of 21621402477270 is 7277420412612.

21621402477270 is a `hidden beast` number, since 2 + 16 + 2 + 140 + 2 + 477 + 27 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 367862985 + ... + 367921755.

It is an arithmetic number, because the mean of its divisors is an integer number (586477089744).

Almost surely, 2^{21621402477270} is an apocalyptic number.

21621402477270 is an abundant number, since it is smaller than the sum of its proper divisors (34680398138154).

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

21621402477270 is a wasteful number, since it uses less digits than its factorization.

21621402477270 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64978 (or 64975 counting only the distinct ones).

The product of its (nonzero) digits is 526848, while the sum is 45.

Adding to 21621402477270 its reverse (7277420412612), we get a palindrome (28898822889882).

The spelling of 21621402477270 in words is "twenty-one trillion, six hundred twenty-one billion, four hundred two million, four hundred seventy-seven thousand, two hundred seventy".