20861834625 has 24 divisors (see below), whose sum is σ = 37606935912. Its totient is φ = 11126311200.

The previous prime is 20861834593. The next prime is 20861834627. The reversal of 20861834625 is 52643816802.

20861834625 is a `hidden beast` number, since 2 + 0 + 8 + 6 + 18 + 3 + 4 + 625 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 77422401 + 20784412224 = 8799^2 + 144168^2 .

It is not a de Polignac number, because 20861834625 - 2⁵ = 20861834593 is a prime.

It is a super-2 number, since 2×20861834625² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (45) 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 (45).

It is not an unprimeable number, because it can be changed into a prime (20861834627) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9270802 + ... + 9273051.

It is an arithmetic number, because the mean of its divisors is an integer number (1566955663).

Almost surely, 2^20861834625 is an apocalyptic number.

20861834625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20861834625 is a deficient number, since it is larger than the sum of its proper divisors (16745101287).

20861834625 is a wasteful number, since it uses less digits than its factorization.

20861834625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18543874 (or 18543861 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 20861834625 in words is "twenty billion, eight hundred sixty-one million, eight hundred thirty-four thousand, six hundred twenty-five".