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99972881 = 234346647
BaseRepresentation
bin1011111010101…
…11011100010001
320222010011000022
411331113130101
5201043113011
613530433225
72322520061
oct575273421
9228104008
1099972881
1151483118
1229592815
1317934368
14d3c53a1
158b9b8db
hex5f57711

99972881 has 4 divisors (see below), whose sum is σ = 104319552. Its totient is φ = 95626212.

The previous prime is 99972877. The next prime is 99972913. The reversal of 99972881 is 18827999.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18827999 = 83922441.

It is a cyclic number.

It is not a de Polignac number, because 99972881 - 22 = 99972877 is a prime.

It is a super-2 number, since 2×999728812 = 19989153870880322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99972871) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2173301 + ... + 2173346.

It is an arithmetic number, because the mean of its divisors is an integer number (26079888).

Almost surely, 299972881 is an apocalyptic number.

99972881 is the 5345-th centered heptagonal number.

It is an amenable number.

99972881 is a deficient number, since it is larger than the sum of its proper divisors (4346671).

99972881 is a wasteful number, since it uses less digits than its factorization.

99972881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4346670.

The product of its digits is 653184, while the sum is 53.

The square root of 99972881 is about 9998.6439580575. The cubic root of 99972881 is about 464.1169211519.

The spelling of 99972881 in words is "ninety-nine million, nine hundred seventy-two thousand, eight hundred eighty-one".

Divisors: 1 23 4346647 99972881