21407364991078 has 32 divisors (see below), whose sum is σ = 35929101312000. Its totient is φ = 9482712106560.

The previous prime is 21407364991049. The next prime is 21407364991091. The reversal of 21407364991078 is 87019946370412.

It is a super-2 number, since 2×21407364991078² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44187078 + ... + 44668921.

It is an arithmetic number, because the mean of its divisors is an integer number (1122784416000).

Almost surely, 2^{21407364991078} is an apocalyptic number.

21407364991078 is a deficient number, since it is larger than the sum of its proper divisors (14521736320922).

21407364991078 is a wasteful number, since it uses less digits than its factorization.

21407364991078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88856292.

The product of its (nonzero) digits is 18289152, while the sum is 61.

The spelling of 21407364991078 in words is "twenty-one trillion, four hundred seven billion, three hundred sixty-four million, nine hundred ninety-one thousand, seventy-eight".